udf: don't increment lenExtents while writing to a hole
udf: don't increment lenExtents while writing to a hole

Incrementing lenExtents even while writing to a hole is bad
for performance as calls to udf_discard_prealloc and
udf_truncate_tail_extent would not return from start if
isize != lenExtents

Signed-off-by: Namjae Jeon <65d484aa1efdaf0ae258f87a04ed8ec8685cba3e@samsung.com>
Signed-off-by: Ashish Sangwan <3e1f6bc3f57a77fb276e7ac9018adc534c863417@samsung.com>
Signed-off-by: Jan Kara <596727c8a0ea4db3ba2ceceedccbacd3d7b371b8@suse.cz>

KristFoundation/Programs,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,TeamVee-Kanas/android_kernel_samsung_kanas