soc: qcom: smp2p: Remove test code

Remove the code responsible for unit testing various aspects on the
smp2p framework. Leave the loopback smp2p code to preserve the
MOCK REMOTE functionality in smp2p.

CRs-Fixed: 2120485
Change-Id: I2031bbc2b49b6f2e12b92db33b9b23e9000c082d
Signed-off-by: Chris Lew <clew@codeaurora.org>