[gdb/testsuite] Simplify gdb.base/info-types.exp.tcl

The regexp matching state machine in gdb.base/info-types.exp.tcl handles
"File .*:" lines individually.  Now that we do line-by-line matching, that's
no longer necessary.

Simplify accordingly.

Tested on x86_64-linux.

gdb/testsuite/ChangeLog:

2021-06-07  Tom de Vries  <tdevries@suse.de>

	* gdb.base/info-types.exp.tcl: Remove "File .*" matching from regexp
	matching state machine.