Add bitfields test from GDB.

	* Makefile.am: Add gdb-bitfiels
	* Makefile.in: Regenerate
	* analysis/simulator.in: Add gdb-bitfields
	* configure: Regenerate
	* configure.ac: Add gdb-bitfiels
	* src/gdb-bitfields/Makefile.am: Create
	* src/gdb-bitfields/Makefile.in: Regenerate
	* src/gdb-bitfields/bitfields.c: Import bitfiels.c from the GDB
	    testsuite
Add store test from GDB.

	* Makefile.am: Add gdb-store
	* Makefile.in: Regenerate
	* analysis/simulator.in: Add gdb-store
	* configure: Regenerate
	* configure.ac: Add gdb-store
	* src/gdb-store/Makefile.am: Create
	* src/gdb-store/Makefile.in: Regenerate
	* src/gdb-store/store.c: Import store.c from the GDB testsuite
Add constvars test from GDB.

	* Makefile.am: Add gdb-constvars
	* Makefile.in: Regenerate
	* analysis/simulator.in: Add gdb-constvars
	* configure: Regenerate
	* configure.ac: Add gdb-constvars
	* src/gdb-constvars/Makefile.am: Create
	* src/gdb-constvars/Makefile.in: Regenerate
	* src/gdb-constvars/constvars.c: Import constvars.c from the GDB
	    testsuite