Don't try building gdb against guile-2.2

Don't try building gdb against guile-2.2

GDB currently doesn't build with Guile 2.2 (see PR 21104).  If one has
both Guile 2.2 and 2.0 installed, GDB will pick up Guile 2.2 first and
fail building.  Until somebody does the work of adapting the GDB code to
Guile 2.2, we should not try using it.  This patch therefore removes it
from configure.

gdb/ChangeLog:

	* configure.ac (try_guile_versions): Remove guile-2.2.
	* configure: Regenerate.