msm: ipa: fix IPA module init failure code to avoid kernel crash

BAM driver will unmap the ioremap performed by IPA driver as
part of sps_deregister_bam_device. IPA driver does not really
need to setup this mapping so remove that code. Also fix clock
cleanup.

Change-Id: I8dcbeb4cc2a025898b4f1d2d813a17a9805d3858
Signed-off-by: Ravi Gummadidala <rgummadi@codeaurora.org>