graphics/libgnomecanvas: unbreak bulk -t build, add missing deps

To fix these poudriere build errors:

[00:01:05] ====> Running Q/A tests (stage-qa)
[00:01:05] Error: /usr/local/lib/libgnomecanvas-2.so.0.3000.3 is linked to /usr/local/lib/libcairo.so.2 from graphics/cairo but it is not declared as a dependency
[00:01:05] Warning: you need USE_GNOME+=cairo
[00:01:05] Error: /usr/local/lib/libgnomecanvas-2.so.0.3000.3 is linked to /usr/local/lib/libgdk_pixbuf-2.0.so.0 from graphics/gdk-pixbuf2 but it is not declared as a dependency
[00:01:05] Warning: you need USE_GNOME+=gdkpixbuf2
[00:01:06] Error: /usr/local/lib/libgnomecanvas-2.so.0.3000.3 is linked to /usr/local/lib/libharfbuzz.so.0 from print/harfbuzz but it is not declared as a dependency
[00:01:06] Warning: you need LIB_DEPENDS+=libharfbuzz.so:print/harfbuzz
[00:01:06] Error: /usr/local/lib/libgnomecanvas-2.so.0.3000.3 is linked to /usr/local/lib/libfontconfig.so.1 from x11-fonts/fontconfig but it is not declared as a dependency
[00:01:06] Warning: you need LIB_DEPENDS+=libfontconfig.so:x11-fonts/fontconfig
[00:01:06] Error: /usr/local/lib/libgnomecanvas-2.so.0.3000.3 is linked to /usr/local/lib/libfreetype.so.6 from print/freetype2 but it is not declared as a dependency
[00:01:06] Warning: you need LIB_DEPENDS+=libfreetype.so:print/freetype2
[00:01:06] ====> Checking for pkg-plist issues (check-plist)
[00:01:06] ===> Parsing plist
[00:01:06] ===> Checking for items in STAGEDIR missing from pkg-plist
[00:01:06] Error: Orphaned: @dir lib/libglade/2.0

Approved by: portmgr@ (blanket)