Update config.m4

Author: cebe

ext/curl/config.m4

@@ -17,19 +17,23 @@ if test "$PHP_CURL" != "no"; then
         break
       fi
     done
-    if which dpkg-architecture; then
-      AC_MSG_CHECKING(for cURL in multiarch path)
-      CURL_MULTIARCH_INCLUDE=/usr/include/$(dpkg-architecture -qDEB_HOST_MULTIARCH)
-      if test -r $CURL_MULTIARCH_INCLUDE/curl/easy.h; then
-        CURL_DIR=/usr
-        AC_MSG_RESULT(found in $CURL_MULTIARCH_INCLUDE)
+    if test -z "$CURL_DIR"; then
+      AC_MSG_RESULT(not found)
+      if which dpkg-architecture>/dev/null; then
+        AC_MSG_CHECKING(for cURL in multiarch path)
+        CURL_MULTIARCH_INCLUDE=/usr/include/$(dpkg-architecture -qDEB_HOST_MULTIARCH)
+        if test -r $CURL_MULTIARCH_INCLUDE/curl/easy.h; then
+          CURL_DIR=/usr
+          AC_MSG_RESULT(found in $CURL_MULTIARCH_INCLUDE)
+        else
+          AC_MSG_RESULT(not found)
+        fi
       fi
     fi
   fi
 
   if test -z "$CURL_DIR"; then
-    AC_MSG_RESULT(not found)
-    AC_MSG_ERROR(Please reinstall the libcurl distribution -
+    AC_MSG_ERROR(Could not find cURL, please reinstall the libcurl distribution -
     easy.h should be in <curl-dir>/include/curl/)
   fi