Add guality [p]type test.

Add guality [p]type test.

Add a new type:var variant to the guality.exp testsuite to check that
gdb gets the correct type for a variable or function. To use it in a
guality test add something like:

/* { dg-final { gdb-test 50 "type:main" "int (int, char **)" } } */

Which will put a breakpoint at line 50 and check that the type of "main"
equals "int (int, char **)" according to gdb. The test harness will make
sure to squash all extra whitespace/newlines that gdb might use to make
comparisons of large structs easy.

gcc/testsuite/ChangeLog

	* lib/gcc-gdb-test.exp (gdb-test): Handle type:var for gdb ptype
	matching. Catch '<unknown type in ' to recognize older gdb versions.
	* gcc.dg/guality/const-volatile.c: New test.

From-SVN: r214139