icp: mark asm files with noexec stack

If there is no explicit note in the .S files, the obj file will mark it
as requiring an executable stack. This is unneeded and causes issues on
hardened systems.

More info:
https://wiki.gentoo.org/wiki/Hardened/GNU_stack_quickstart

Signed-off-by: Jason Zaman <jason@perfinion.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #4947
Closes #4962

module/icp/asm-x86_64/aes/aes_amd64.S

@@ -898,3 +898,7 @@ dec_tab:
 
 	SET_SIZE(aes_decrypt_amd64)
 #endif	/* lint || __lint */
+
+#ifdef __ELF__
+.section .note.GNU-stack,"",%progbits
+#endif

module/icp/asm-x86_64/aes/aes_intel.S

@@ -849,3 +849,7 @@ ENTRY_NP(aes_decrypt_intel)
 	SET_SIZE(aes_decrypt_intel)
 
 #endif	/* lint || __lint */
+
+#ifdef __ELF__
+.section .note.GNU-stack,"",%progbits
+#endif

module/icp/asm-x86_64/modes/gcm_intel.S

@@ -332,3 +332,7 @@ ENTRY_NP(gcm_mul_pclmulqdq)
 	SET_SIZE(gcm_mul_pclmulqdq)
 
 #endif	/* lint || __lint */
+
+#ifdef __ELF__
+.section .note.GNU-stack,"",%progbits
+#endif

module/icp/asm-x86_64/sha1/sha1-x86_64.S

@@ -1344,3 +1344,7 @@ SET_SIZE(sha1_block_data_order)
 .asciz	"SHA1 block transform for x86_64, CRYPTOGAMS by <appro@openssl.org>"
 
 #endif /* lint || __lint */
+
+#ifdef __ELF__
+.section .note.GNU-stack,"",%progbits
+#endif

module/icp/asm-x86_64/sha2/sha256_impl.S

@@ -2058,3 +2058,7 @@ K256:
 	.long	0x748f82ee,0x78a5636f,0x84c87814,0x8cc70208
 	.long	0x90befffa,0xa4506ceb,0xbef9a3f7,0xc67178f2
 #endif /* !lint && !__lint */
+
+#ifdef __ELF__
+.section .note.GNU-stack,"",%progbits
+#endif