soc: qcom: remoteqdss: Implement the remaining message types

Implement the tag, swevent, and swentity message formats.
Additionally, abstract the actual scm call and error checking
into a separate shared function.

CRs-Fixed: 997749
Change-Id: Ie80846978a84a114b38d69b0bca86639bfab7e91
Signed-off-by: Patrick Daly <pdaly@codeaurora.org>