system/gtk-vnc: Enforced -j1 clearing jobs call from the MAKEFLAGS.

Signed-off-by: Matteo Bernardini <ponce@slackbuilds.org>

system/gtk-vnc/gtk-vnc.SlackBuild

@@ -6,7 +6,7 @@
 
 PRGNAM=gtk-vnc
 VERSION=${VERSION:-0.5.1}
-BUILD=${BUILD:-1}
+BUILD=${BUILD:-2}
 TAG=${TAG:-_SBo}
 
 # Automatically determine the architecture we're building on:
@@ -57,6 +57,9 @@ find $PRGNAM-$VERSION \
  \( -perm 666 -o -perm 664 -o -perm 600 -o -perm 444 -o -perm 440 -o -perm 400 \) \
  -exec chmod 644 {} \;
 
+# Cut away jobs number from the MAKEFLAGS
+MAKEFLAGS=$(echo "$MAKEFLAGS" | sed "s/-j[0-999]//g")
+
 # We will build both the gtk+3 and gtk+2 libs with -j1 to avoid surprises
 # To avoid building the gtk3 version, pass GTK3=no to the script
 if [ "${GTK3:-yes}" = "yes" ]; then