Remove dependency on asm/hwcap.h

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>

library/sha256.c

@@ -126,7 +126,13 @@
 #      if defined(__linux__)
 /* Our preferred method of detection is getauxval() */
 #        include <sys/auxv.h>
-#        include <asm/hwcap.h>
+/* These are not always defined via sys/auxv.h */
+#        if !defined(HWCAP_SHA2)
+#          define HWCAP_SHA2  (1 << 6)
+#        endif
+#        if !defined(HWCAP2_SHA2)
+#          define HWCAP2_SHA2 (1 << 3)
+#        endif
 #      endif
 /* Use SIGILL on Unix, and fall back to it on Linux */
 #      include <signal.h>

tests/scripts/all.sh

@@ -4344,10 +4344,7 @@ support_build_sha_armce() {
         # clang >= 4 is required to build with SHA extensions
         clang_ver="$(clang --version|grep version|sed -E 's#.*version ([0-9]+).*#\1#')"
 
-        # we need asm/hwcap.h available for runtime detection
-        echo '#include <asm/hwcap.h>' | clang -E - >/dev/null 2>&1 && have_hwcap=1 || have_hwcap=0
-
-        [[ "${clang_ver}" -ge 4 && "${have_hwcap}" -eq 1 ]]
+        [[ "${clang_ver}" -ge 4 ]]
     else
         # clang not available
         false