rgblight.c: add remap feature

[mtei]

Description

Added support for RGBLIGHT_LED_MAP macro to rgblight.c.

Example 1:

// config.h

#define RGBLED_NUM 10
#define RGBLIGHT_LED_MAP { 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 }

Example 2:

// config.h

#define RGBLED_NUM 30

/* RGB LED Conversion macro from physical array to electric array */
#define LED_LAYOUT( \
    L00, L01, L02, L03, L04, L05,  \
    L10, L11, L12, L13, L14, L15,  \
    L20, L21, L22, L23, L24, L25,  \
    L30, L31, L32, L33, L34, L35,  \
    L40, L41, L42, L43, L44, L45 ) \
  { \
    L05, L04, L03, L02, L01, L00,   \
    L10, L11, L12, L13, L14, L15,   \
    L25, L24, L23, L22, L21, L20,   \
    L30, L31, L32, L33, L34, L35,   \
    L46, L45, L44, L43, L42, L41    \
  }

/* RGB LED logical order map */
/* Top->Bottom, Right->Left */
#define RGBLIGHT_LED_MAP LED_LAYOUT( \
  25, 20, 15, 10,  5,  0,       \
  26, 21, 16, 11,  6,  1,       \
  27, 22, 17, 12,  7,  2,       \
  28, 23, 18, 13,  8,  3,       \
  29, 24, 19, 14,  9,  4 )

On a keyboard that uses the RGB LEDs as a backlight for each key, this macro helps to light the corresponding LED when the key is pressed.

Types of Changes

• Core
• Bugfix
• New feature
• Enhancement/optimization
• Keyboard (addition or update)
• Keymap/layout/userspace (addition or update)
• Documentation

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• I have tested the changes and verified that they work and don't break anything (as well as I can manage).

[mechmerlin]

Thanks!