soc: qcom: glink_smd_xprt: add SMD channel open error handling

If the SMD channel fails to open, it is silent leading to hard-to-debug
issues.

Add logging of SMD channel open failure.

Change-Id: Icc39ba8d666089ab864c8d4b66d269b7d6287048
Signed-off-by: Eric Holmberg <eholmber@codeaurora.org>