staging: sm7xxfb: minor maintenance on timing path
staging: sm7xxfb: minor maintenance on timing path

This patch keeps smtc_set_timing and sm7xx_set_timing functions closed
to smtcfb_setmode. This change eases reviewing and maintaining this
logic path.

Tested with SM712.

Signed-off-by: Javier M. Mellid <d98556cef8d7a8ae4702341548cf34e07ca3c02f@igalia.com>
Signed-off-by: Greg Kroah-Hartman <4645f7897fd33786a2ee1264d590b3c400559d85@linuxfoundation.org>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas