msm: cleanup: union gsi_evt_scratch

Remove __packed from the usage of union gsi_evt_scratch.
__packed is only needed in the union definition.

include/linux/msm_gsi.h:
union __packed gsi_evt_scratch {
    ...
}

Bug: 139442076
Bug: 139808631
Change-Id: If3d0e1bc2674f01d5a9a02e73d33b28a648539bc
Signed-off-by: Petri Gynther <pgynther@google.com>
Signed-off-by: UtsavBalar1231 <utsavbalar1231@gmail.com>
Signed-off-by: danascape <saalim.priv@gmail.com>
Signed-off-by: danascape <danascape@gmail.com>