target/Config.in.arch: provide correct gcc --with-arch= for ARM targets

Updated to match gcc-4.3.3/gcc/config/arm/arm-cores.def.
Should fix EABI issues as recently reported to the list.

target/Config.in.arch

@@ -655,6 +655,20 @@ config BR2_GCC_TARGET_ARCH
 	default winchip2	if BR2_x86_winchip2
 	default c3		if BR2_x86_c3
 	default geode		if BR2_x86_geode
+	default armv4t		if BR2_arm7tdmi
+	default arm3		if BR2_arm610
+	default arm3		if BR2_arm710
+	default arm4t		if BR2_arm720t
+	default arm4t		if BR2_arm920t
+	default arm4t		if BR2_arm922t
+	default arm4t		if BR2_arm926t
+	default arm5t		if BR2_arm10t
+	default arm6j		if BR2_arm1136jf_s
+	default arm6zk		if BR2_arm1176jz_s
+	default arm6zk		if BR2_arm1176jzf_s
+	default arm4		if BR2_sa110
+	default arm4		if BR2_sa1100
+	default arm5te		if BR2_xscale
 	default iwmmxt		if BR2_iwmmxt
 	default v0		if BR2_cris_unknown
 	default v10		if BR2_cris_generic