diag: Featurize IPC logging under IPC_LOGGING config

Currently, in case IPC logging related config
is disabled then there are some unwanted error
logs in kernel logs. Featurize IPC logging under
IPC_LOGGING config to get rid of error logs.

Change-Id: I8455f5e3a13cf58b4d65d1e1a5c4f1ec0adedabf
Signed-off-by: Mohit Aggarwal <maggarwa@codeaurora.org>