fs: skip read-only remount of mmcblk0p19 by OliverG96

-From https://github.com/Team-Exhibit/android_kernel_samsung_common/commit/13a75b9348a8c0b5c3845821f5421b93d28aa7fe
defconfig: don't use Samsung MTP and Composite

-MTP: see https://github.com/Meticulus/android_kernel_samsung_codinatmo/blob/kk44/drivers/usb/gadget/android.c#L59

-Composite: see https://github.com/Meticulus/android_kernel_samsung_codinatmo/blob/kk44/drivers/usb/gadget/composite.c#L270

NOTE: Samsung MTP and Composite probably work well on stock ROMs but
for others we need defaults.