gtk-icon-cache: don't call gtk-update-icon-cache on files
* check if icondir is directory before calling gtk-update-icon-cache, like all other calls do
* fixes:
| > Executing update_icon_cache
| + chmod +x update_icon_cache
| + ./update_icon_cache
| gtk-update-icon-cache.real: Failed to open file /tmp-eglibc/work/qemuarm-oe-linux-gnueabi/shr-image-all/2.0-r20/rootfs/usr/share/icons/enjoy.png/.icon-theme.cache : Not a directory
| gtk-update-icon-cache.real: Failed to open file /tmp-eglibc/work/qemuarm-oe-linux-gnueabi/shr-image-all/2.0-r20/rootfs/usr/share/icons/monav.png/.icon-theme.cache : Not a directory
| gtk-update-icon-cache.real: Failed to open file /tmp-eglibc/work/qemuarm-oe-linux-gnueabi/shr-image-all/2.0-r20/rootfs/usr/share/icons/orrery.png/.icon-theme.cache : Not a directory
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com> Signed-off-by: Saul Wold <sgw@linux.intel.com>
