contra, fractal: Remove wrongly copypasted pin E6 manipulation code (#14818)

Apparently the default keymaps for `contra` and `fractal` were derived
from some `planck` keymap which contained code to control the status LED
in the implementation of the `BACKLIT` custom keycode.  Unfortunately,
the code to control the LED manipulated the `E6` pin directly, and it
was copied without changes, but the `contra` and `fractal` boards use
the `E6` pin in the matrix, therefore pressing the key mapped to
`BACKLIT` resulted in phantom keypresses for all keys in the
corresponding column.

keyboards/contra/keymaps/default/keymap.c

@@ -222,10 +222,8 @@ bool process_record_user(uint16_t keycode, keyrecord_t *record) {
         #ifdef BACKLIGHT_ENABLE
           backlight_step();
         #endif
-        PORTE &= ~(1<<6);
       } else {
         unregister_code(KC_RSFT);
-        PORTE |= (1<<6);
       }
       return false;
       break;