* Makefile.in: Derive SHELL from configure.

	* Makefile.in:  Derive SHELL from configure.
	* config/d10v/d10v.mt config/d30v/d30v.mt config/m32r/m32r.mt
	config/mn10200/mn10200.mt config/mn10300/mn10300.mt :  Remove -lm
	from SIM.  This prevents dependency checking of -lm (under NT
	native builds).  (It is automatically added by configure if it
	exists.)
	* doc/configure mswin/configure nlm/configure
	testsuite/gdb.base/configure testsuite/gdb.c++/configure
	testsuite/gdb.chill/configure testsuite/gdb.disasm/configure
	testsuite/gdb.stabs/configure testsuite/gdb.threads/configure:
	Regenerate with autoconf 2.12.1 to fix shell issues for NT native
	builds.