configure: arm/aarch64: allow enable-seccomp

This is a revert of ae6e8ef1, but with a bit of refactoring,
and also specifically adding arm/aarch64, rather than all
architectures. Currently, libseccomp code appears to also support
mips, ppc, and s390. We could therefore allow qemu to enable
seccomp for those platforms as well, with additional configure
patches, given they're tested and proven to work.
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Acked-by: NEduardo Otubo <eduardo.otubo@profitbricks.com>

configure

@@ -1888,16 +1888,34 @@ fi
 # libseccomp check
 
 if test "$seccomp" != "no" ; then
-    if test "$cpu" = "i386" || test "$cpu" = "x86_64" &&
-        $pkg_config --atleast-version=2.1.1 libseccomp; then
+    case "$cpu" in
+    i386|x86_64)
+        libseccomp_minver="2.1.1"
+        ;;
+    arm|aarch64)
+        libseccomp_minver="2.2.3"
+        ;;
+    *)
+        libseccomp_minver=""
+        ;;
+    esac
+
+    if test "$libseccomp_minver" != "" &&
+       $pkg_config --atleast-version=$libseccomp_minver libseccomp ; then
         libs_softmmu="$libs_softmmu `$pkg_config --libs libseccomp`"
         QEMU_CFLAGS="$QEMU_CFLAGS `$pkg_config --cflags libseccomp`"
-	seccomp="yes"
+        seccomp="yes"
     else
-	if test "$seccomp" = "yes"; then
-            feature_not_found "libseccomp" "Install libseccomp devel >= 2.1.1"
-	fi
-	seccomp="no"
+        if test "$seccomp" = "yes" ; then
+            if test "$libseccomp_minver" != "" ; then
+                feature_not_found "libseccomp" \
+                    "Install libseccomp devel >= $libseccomp_minver"
+            else
+                feature_not_found "libseccomp" \
+                    "libseccomp is not supported for host cpu $cpu"
+            fi
+        fi
+        seccomp="no"
     fi
 fi
 ##########################################