Or bit_Prefer_MAP_32BIT_EXEC in EXTRA_LD_ENVVARS

We should turn on bit_Prefer_MAP_32BIT_EXEC in EXTRA_LD_ENVVARS without
overriding other bits.

	[BZ #19758]
	* sysdeps/unix/sysv/linux/x86_64/64/dl-librecon.h
	(EXTRA_LD_ENVVARS): Or bit_Prefer_MAP_32BIT_EXEC.
3 files changed