New asm directory arm/v6. Moved aes functions using the uxtb instruction there.

ChangeLog

+2013-05-15  Niels Möller  <nisse@lysator.liu.se>
+
+	* configure.ac (asm_path): Handle armv6 and armv7 differently from
+	older ARMs. Add the arm/v6 directory to asm_path when appropriate.
+
+	* arm/v6/aes-encrypt-internal.asm: Moved into v6 directory. Uses
+	the uxtb instruction which is not available for older ARMs.
+	* arm/v6/aes-decrypt-internal.asm: Likewise.
+
 2013-05-03  Niels Möller  <nisse@lysator.liu.se>
 
 	* cast128.c: Adapt to new struct cast128_ctx.

configure.ac

@@ -237,14 +237,18 @@ if test "x$enable_assembler" = xyes ; then
 	asm_path=sparc32
       fi
       ;;
-    arm*)
+    armv6* | armv7*)
       NETTLE_CHECK_ARM_NEON
 
-      asm_path=arm
+      asm_path="arm/v6 arm"
+      
       if test "x$enable_arm_neon" = xyes ; then
 	asm_path="arm/neon $asm_path"
       fi
       ;;
+    arm*)
+      asm_path=arm
+      ;;
     *)
       enable_assembler=no
       ;;