Accept iOS SDK 12.2

Change-Id: Ie3eae75f13d27f3fce11acb66073dd51c0d41a32
diff --git a/configure.ac b/configure.ac
index 8a3f1e2..0a8c1a5 100644
--- a/configure.ac
+++ b/configure.ac
@@ -2962,8 +2962,8 @@ dnl ===================================================================

if test $_os = iOS; then
    AC_MSG_CHECKING([what iOS SDK to use])
    current_sdk_ver=12.1
    older_sdk_vers="12.0 11.4"
    current_sdk_ver=12.2
    older_sdk_vers="12.1 12.0 11.4"
    if test "$enable_ios_simulator" = "yes"; then
        platform=iPhoneSimulator
        versionmin=-mios-simulator-version-min=11.0