[gdb/testsuite] Fix gdb.opt/inline-locals.exp KFAILs

When running test-case gdb.opt/inline-locals.exp, I get:
...
Running src/gdb/testsuite/gdb.opt/inline-locals.exp ...
KPASS: gdb.opt/inline-locals.exp: info locals above bar 2 (PRMS gdb/xyz)
KPASS: gdb.opt/inline-locals.exp: info locals above bar 3 (PRMS gdb/xyz)
...

I've opened PR25695 - 'abstract and concrete variable listed both with "info
locals"' to refer to in the PRMS field, and this patch adds that reference.

Furthermore, I noticed that while I see KPASSes, given the problem description
the tests should actually be KFAILs.  This patch also fixes that.

Tested on x86_64-linux.  With gcc 7.5.0, I get 2 KFAILs.  With clang 5.0.2,
the tests pass.

gdb/testsuite/ChangeLog:

2020-03-19  Tom de Vries  <tdevries@suse.de>

	* gdb.opt/inline-locals.exp: Add kfail PR number.  Make kfail matching
	more precise.