XFCE: Cleanup dependencies

• Update xfce.mk to avid forcing too many dependencies on consumers
• Change dependency on garcon to reference libgarcon-1.so (main library)
• Explicitly add USE_XFCE components to the ports actually needing them.
• Cleanup dependencies, adding/removing missing/extra dependencies
• Change the referenced library in some LIB_DEPENDS to the actually linked one (avoids false positives in poudriere Q/A tests)
• Bump PORTREVISION on all touched ports, even indirectly due to the effect of removing forced dependencies on certain components
• Remove USES=fuse from gigolo. I could not find any kind f reference to fuse in the code.
• xfce4-bsdcpufreq-plugin: Also remove empty comment at the top of the Makefile