aes/asm/*-armv*.pl: compensate for inconsistencies in tool-chains.

Suggested by: Ard Biesheuvel

crypto/aes/asm/aes-armv4.pl

@@ -62,6 +62,11 @@ $code=<<___;
 .code	32
 #else
 .syntax	unified
+# ifdef __thumb2__
+.thumb
+# else
+.code	32
+# endif
 #endif
 
 .type	AES_Te,%object

crypto/aes/asm/bsaes-armv7.pl

@@ -652,6 +652,12 @@ $code.=<<___;
 #if __ARM_ARCH__>=7
 .text
 .syntax	unified 	@ ARMv7-capable assembler is expected to handle this
+#ifdef __thumb2__
+.thumb
+#else
+.code   32
+#endif
+
 .fpu	neon
 
 .type	_bsaes_decrypt8,%function