kgdb: kdmx agent-proxy: clean up error messages

Clean up some areas that will be impacted by patches later in the series
   - replace mis-used perror() with pr_err()
   - clean up perror() strings, for consistency and brevity
   - ensure all error and warning strings are unique
   - correct one word in usage()

Signed-off-by: Frank Rowand <frank.rowand@sonymobile.com>
Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
1 file changed