Fixed WebRTC build failure on iOS (#4423)

Author: sauwming

aconfigure

@@ -11081,7 +11081,7 @@ printf "%s\n" "Checking if libwebrtc is disabled...no" >&6; }
         case $target in
             *-apple-darwin_ios*)
                 case $target in
-                    arm64*)
+                    arm64* | aarch64*)
                         ac_webrtc_instset=neon
                         ac_webrtc_cflags="-DWEBRTC_ARCH_ARM64"
                     ;;
@@ -11234,7 +11234,7 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
             case $target in
                 *-apple-darwin_ios*)
                     case $target in
-                        arm64*)
+                        arm64* | aarch64*)
                             ac_webrtc_aec3_instset=neon
                             ac_webrtc_aec3_cflags="-DWEBRTC_ARCH_ARM64"
                         ;;

aconfigure.ac

@@ -2717,7 +2717,7 @@ AC_ARG_ENABLE(libwebrtc,
         case $target in
             *-apple-darwin_ios*)
                 case $target in
-                    arm64*)
+                    arm64* | aarch64*)
                         ac_webrtc_instset=neon
                         ac_webrtc_cflags="-DWEBRTC_ARCH_ARM64"
                     ;;
@@ -2837,7 +2837,7 @@ AC_ARG_ENABLE(libwebrtc_aec3,
             case $target in
                 *-apple-darwin_ios*)
                     case $target in
-                        arm64*)
+                        arm64* | aarch64*)
                             ac_webrtc_aec3_instset=neon
                             ac_webrtc_aec3_cflags="-DWEBRTC_ARCH_ARM64"
                         ;;