USB: Handle allocated buffer freeing after error and unused variables

Free the allocated buffer after an error and remove
unused variables.

CRs-Fixed: 313681
Change-Id: I76ebf946eacac47682a3c510cd7beed3fc3c6437
Signed-off-by: Rajkumar Raghupathy <raghup@codeaurora.org>
3 files changed