msm: kgsl: Do not cause a fatal error on request firmware failure

request_firmware() can fail sometimes.  If it does propagate the
error up and fail the open request and do not trigger a fatal
error.

Change-Id: I0adcd21ad6a1d50be2f374b0a88537a705c58b1f
Signed-off-by: Tarun Karra <tkarra@codeaurora.org>