Fix pcre.jit on Apple Silicon

This backports zherczeg/sljit#105. Relates to bug #80435, however, it doesn't solve the bus error on PHP 8.0, but PHP 8.1 builds fine now.

Closes GH-9279.

Author: kelunik

NEWS

@@ -18,6 +18,9 @@ PHP                                                                        NEWS
   . Fixed bug #77780 ("Headers already sent..." when previous connection was
     aborted). (Jakub Zelenka)
 
+- PCRE:
+  . Fixed pcre.jit on Apple Silicon. (Niklas Keller)
+
 - Streams:
   . Fixed bug GH-9316 ($http_response_header is wrong for long status line).
     (cmb, timwolla)

ext/pcre/pcre2lib/sljit/sljitExecAllocator.c

@@ -187,10 +187,13 @@ static SLJIT_INLINE void* alloc_chunk(sljit_uw size)
 	if (retval == MAP_FAILED)
 		return NULL;
 
+#ifdef __FreeBSD__
+	/* HardenedBSD's mmap lies, so check permissions again */
 	if (mprotect(retval, size, PROT_READ | PROT_WRITE | PROT_EXEC) < 0) {
 		munmap(retval, size);
 		return NULL;
 	}
+#endif /* FreeBSD */
 
 	SLJIT_UPDATE_WX_FLAGS(retval, (uint8_t *)retval + size, 0);