rpm/check-for-config-changes: add OBJTOOL and FTRACE_MCOUNT_USE_*
Dummy gcc pretends to support -mrecord-mcount option but actual gcc on
ppc64le does not. Therefore ppc64le builds of 6.2-rc1 and later in OBS
enable FTRACE_MCOUNT_USE_OBJTOOL and OBJTOOL config options, resulting in
check failure.
As we already have FTRACE_MCOUNT_USE_CC and FTRACE_MCOUNT_USE_RECORDMCOUNT
in the exception list, replace them with a general pattern. And add OBJTOOL
as well.