Fixed finding CURL on systems with multiarch support

fixes https://bugs.php.net/bug.php?id=74125

Author: cebe

ext/curl/config.m4

@@ -17,6 +17,14 @@ 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)
+      fi
+    fi
   fi
 
   if test -z "$CURL_DIR"; then
@@ -45,7 +53,11 @@ if test "$PHP_CURL" != "no"; then
     AC_MSG_ERROR(cURL version 7.10.5 or later is required to compile php with cURL support)
   fi
 
-  PHP_ADD_INCLUDE($CURL_DIR/include)
+  if test -z "$CURL_MULTIARCH_INCLUDE"; then
+    PHP_ADD_INCLUDE($CURL_DIR/include)
+  else
+    PHP_ADD_INCLUDE($CURL_MULTIARCH_INCLUDE)
+  fi
   PHP_EVAL_LIBLINE($CURL_LIBS, CURL_SHARED_LIBADD)
   PHP_ADD_LIBRARY_WITH_PATH(curl, $CURL_DIR/$PHP_LIBDIR, CURL_SHARED_LIBADD)