[cairo] compilation issue re. fontconfig

[Abraham Egnor]

When trying to compile a recently checked out copy of cairo, I hit
this compile error:

cairo_ft_font.c: In function `_get_load_flags':
cairo_ft_font.c:507: error: `FC_HINT_STYLE' undeclared (first use in
this function)
(...etc...)

Doing some digging, I found that the various FC_HINT_* constants are
only present in the development branch of fontconfig.  Perhaps a check
should be added to the cairo autoconf scripts to make sure the version
number of a found fontconfig library is high enough?

Abe