android-configure.sh: Fix GLES auto-detection.

If android-configure.sh didn't find GL emulation headers and
libraries, it would complain but fail to disable it for the
current build. This patch fixes this.
diff --git a/android-configure.sh b/android-configure.sh
index ad77bd2..36b5e9a 100755
--- a/android-configure.sh
+++ b/android-configure.sh
@@ -599,7 +599,7 @@
     echo "HOST_OS   := windows" >> $config_mk
 fi
 
-if [ "$GLES_INCLUDE" -a "$GLES_LIBS" ]; then
+if [ "$GLES_SUPPORT" = "yes" -a "$GLES_INCLUDE" -a "$GLES_LIBS" ]; then
     echo "QEMU_OPENGLES_INCLUDE    := $GLES_INCLUDE" >> $config_mk
     echo "QEMU_OPENGLES_LIBS       := $GLES_LIBS"    >> $config_mk
 fi
@@ -725,7 +725,7 @@
 
 echo "#define CONFIG_ANDROID       1" >> $config_h
 
-if [ "$GLES_INCLUDE" -a "$GLES_LIBS" ]; then
+if [ "$GLES_SUPPORT" = "yes" ]; then
     echo "#define CONFIG_ANDROID_OPENGLES 1" >> $config_h
 fi