UBI: cleanup comments about corrupted PEBs
UBI: cleanup comments about corrupted PEBs

Just make them a bit more readable and explanatory.

Signed-off-by: Artem Bityutskiy <19b5733dcea388885746d36043d3568bba5b4df7@nokia.com>

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