msm: npu: Add support to get firmware capabilities

Add new property ID MSM_NPU_PROP_ID_FW_GETCAPS to retrieve firmware
capabilities. In order to allow get/set firmware property when no
network is loaded, firmware will be enabled before sending command
to firmware and disabled after.

Change-Id: I13846e087e5200fbb5402431ad61692faf97b141
Signed-off-by: Jilai Wang <jilaiw@codeaurora.org>