Update LED/RGB Matrix flag function behavior (#17651)

quantum/led_matrix/led_matrix.h

@@ -158,6 +158,7 @@ void        led_matrix_decrease_speed(void);
 void        led_matrix_decrease_speed_noeeprom(void);
 led_flags_t led_matrix_get_flags(void);
 void        led_matrix_set_flags(led_flags_t flags);
+void        led_matrix_set_flags_noeeprom(led_flags_t flags);
 
 typedef struct {
     /* Perform any initialisation required for the other driver functions to work. */