Patch to enable --with-multilib-list for arm-none-eabi target

["Terry Guo" <terry dot guo at arm dot com>]

Hello,

This patch provides a bunch of predefined MULTILIB for various arm-none-eabi
targets. The MULTILIB_EXCEPTIONS isn't needed because the patch takes
advantage of the new term MULTILIB_REQUIRED which is introduced at
http://gcc.gnu.org/ml/gcc-patches/2012-04/msg00975.html. The existing
configure option --with-multilib-list is enabled as an interface for user to
specify needed libraries from the predefined set. For example if only need
to build Multilib for targets armv7-m and armv7e-m, then the gcc can be
configured with --with-multilib-list=armv7-m,armv7e-m.

Please note that the predefined Multilib set in this patch doesn't cover all
possible cases like big-endian version Multilib. User can extend this set
and just build needed ones through --with-multili-list. So far this patch
can recognize armv6-m, armv7-m, armv7e-m, armv7-r and armv7-a as the options
used in --with-multilib-list.

Tested on trunk for arm-none-eabi target. Is it ok to trunk?

BR,
Terry

2012-05-02  Terry Guo  <terry.guo@arm.com>
	
	* config.gcc: Include more MULTILIB implementations for ARM EABI.
	* config/arm/t-mlibs: New file to define more MULTILIB 
      implementations for ARM targets.
	* configure.ac: Enable --with-multilib-list for ARM 
      and export it for being used in Makefile.in.
	* configure: Regenerated.	
	* Makefile.in: Import configure option --with-multilib-list.

Attachment: enable-with-multilib-list-for-arm.patch
Description: Binary data