expr.c (expand_expr_real_1): Correctly handle strict volatile bitfield loads smaller than mode size.

2011-11-20  Joey Ye  <joey.ye@arm.com>

	* expr.c (expand_expr_real_1): Correctly handle strict volatile
	bitfield loads smaller than mode size.

testsuite:

	* gcc.dg/volatile-bitfields-1.c: New.

From-SVN: r181549