Fix mingw32 failures due to incorrect directory separator in pattern

Fix mingw32 failures due to incorrect directory separator in pattern

Some testcases, mostly gdb.reverse ones, assume the presence of a
'/' directory separator before the source file name. This is
incorrect for mingw32 hosts, generating false failures for those
tests.

I attempted to catch most of the occurrences of the pattern
".*/$srcfile" and replaced them with ".*$srcfile". The latter
is used elsewhere in the testsuite. The resulting patch is attached.

I also see other occurrences of the same assumption throughout the
testsuite, but usually they are arguments for function calls and i
seem to recall either the test harness or GDB deals with those
paths properly.

gdb/testsuite:

2014-10-17  Luis Machado  <lgustavo@codesourcery.com>

	* gdb.guile/scm-breakpoint.exp: Do not assume any
	directory separators when matching source file paths.
	* gdb.python/py-breakpoint.exp: Likewise.
	* gdb.reverse/break-precsave.exp: Likewise.
	* gdb.reverse/break-reverse.exp: Likewise.
	* gdb.reverse/consecutive-precsave.exp: Likewise.
	* gdb.reverse/finish-precsave.exp: Likewise.
	* gdb.reverse/finish-reverse-bkpt.exp: Likewise.
	* gdb.reverse/finish-reverse.exp: Likewise.
	* gdb.reverse/i386-precsave.exp: Likewise.
	* gdb.reverse/i387-env-reverse.exp: Likewise.
	* gdb.reverse/i387-stack-reverse.exp: Likewise.
	* gdb.reverse/machinestate-precsave.exp: Likewise.
	* gdb.reverse/machinestate.exp: Likewise.
	* gdb.reverse/sigall-precsave.exp: Likewise.
	* gdb.reverse/solib-precsave.exp: Likewise.
	* gdb.reverse/step-precsave.exp: Likewise.
	* gdb.reverse/until-precsave.exp: Likewise.
	* gdb.reverse/watch-precsave.exp: Likewise.
	* gdb.reverse/watch-reverse.exp: Likewise.