[Keyboard] Update Symmetric70 keyboard prototype (#12707)

* update handwired/symmetric70_proto/matrix.c

* make keyboards/handwired/symmetric70_proto/promicro/

* add symmetric70_proto/debug_config.h, update symmetric70_proto/local_features.mk etc.

  set MATRIX_IO_DELAY macro
    make MTEST=mdelay0  symmetric70_proto/promicro:default:flash
    make MTEST=mdelay1  symmetric70_proto/promicro:default:flash
    make MTEST=mdelay10 symmetric70_proto/promicro:default:flash
    make MTEST=mdelay30 symmetric70_proto/promicro:default:flash
  set DEBUG_MATRIX_SCAN_RATE_ENABLE yes
    make MTEST=scan symmetric70_proto/promicro:default:flash
  set MATRIX_DEBUG_DELAY and MATRIX_IO_DELAY macro
    make MTEST=matrix_debug_delay,mdelay0 symmetric70_proto/promicro:default:flash
  set MATRIX_DEBUG_SCAN
    make MTEST=matrix_debug_scan symmetric70_proto/promicro:default:flash

* add symmetric70_proto/matrix_debug/readme.md

* update symmetric70_proto/matrix_debug/readme.md

* update handwired/symmetric70_proto/readme.md

* update handwired/symmetric70_proto/readme.md

* update handwired/symmetric70_proto/*/readme.md

* add handwired/symmetric70_proto/matrix_fast/

* update handwired/symmetric70_proto/matrix_fast/readme.md

* fix typo in handwired/symmetric70_proto/matrix_fast/readme.md

* update config.h under handwired/symmetric70_proto/promicro

* add Proton C support to handwired/symmetric70_proto

* add handwired/symmetric70_proto/proton_c/readme.md

* add promicro/*/readme.md proton_c/*/readme.md

* update handwired/symmetric70_proto/proton_c/proton_c.c

support MATRIX_IO_DELAY_DEFAULT for testing.

* Added another implementation of 'adaptive_delay'.

* update symmetric70_proto/local_features.mk

* update symmetric70_proto/matrix_fast/gpio_extr.h

* add matrix_output_unselect_delay_ports()

* add MTEST=adaptive_delay_fast option

* update symmetric70_proto/matrix_debug/readme.md

* update symmetric70_proto/matrix_fast/readme.md

* update symmetric70_proto/matrix_debug/readme.md

* Erase garbage

* fix symmetric70_proto/proton_c/proton_c.c

* improve adaptive_delay_fast in symmetric70_proto/matrix_debug/matrix.c

* update symmetric70_proto/matrix_debug/readme.md

* fix symmetric70_proto/matrix_debug/readme.md

* Update keyboards/handwired/symmetric70_proto/proton_c/rules.mk

Co-authored-by: Ryan <fauxpark@gmail.com>

* Update keyboards/handwired/symmetric70_proto/proton_c/rules.mk

Co-authored-by: Ryan <fauxpark@gmail.com>

* Update keyboards/handwired/symmetric70_proto/local_features.mk

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/local_features.mk

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/matrix_debug/matrix.c

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/matrix_debug/matrix.c

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/local_features.mk

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/matrix_debug/matrix.c

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/matrix_debug/readme.md

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/matrix_debug/readme.md

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/matrix_debug/readme.md

Co-authored-by: Nick Brassel <nick@tzarc.org>

* Update keyboards/handwired/symmetric70_proto/matrix_fast/matrix_config_expand.c

Co-authored-by: Nick Brassel <nick@tzarc.org>

Co-authored-by: Ryan <fauxpark@gmail.com>
Co-authored-by: Nick Brassel <nick@tzarc.org>

keyboards/handwired/symmetric70_proto/proton_c/proton_c.c

@@ -0,0 +1,12 @@
+#include "quantum.h"
+
+#ifndef MATRIX_IO_DELAY_DEFAULT
+/* In tmk_core/common/wait.h, the implementation for PROTOCOL_CHIBIOS
+ * calls 'chThdSleepMicroseconds(1)' when 'wait_us(0)'.
+ * However, 'wait_us(0)' should do nothing. */
+void matrix_output_unselect_delay(void) {
+#   if !defined(MATRIX_IO_DELAY) || MATRIX_IO_DELAY > 0
+    matrix_io_delay();
+#   endif
+}
+#endif