usb: ks_bridge: Fix bug in partial read on data buffer
usb: ks_bridge: Fix bug in partial read on data buffer

If driver copies only partial data buffer to user space
it does not update the buffer pointer. In this case
buffer pointer is still pointing to the already read
buffer and will be copied again in next read request
from user space. This corrupts the contents of the
efs file or ram dump files. Hence update data buffer
pointer with length of memory read completed by user
space.

CRs-Fixed: 403250
Change-Id: I48217aeeb2ee5ad05089922c6a7793195b95ce0c
Signed-off-by: Hemant Kumar <427b3e89cfa4833e90373054043f85c2b5772665@codeaurora.org>

TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas