clang complained (correctly):
warning: comparison of constant 768614336404564650 with expression
of type 'CARD32' (aka 'unsigned int') is always true
[-Wtautological-constant-out-of-range-compare]

[While LONG_MAX is correct, since it's used in size_t math, the
 numbers have to be limited to 32-bit range to be usable by 32-bit
 clients, and values beyond that range are far more likely to be
 bugs in the data from the server than valid numbers of characters
 in a font.   -alan- ]
Reviewed-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Backported-to-NX-by: Ulrich Sibiller <uli42@gmx.de>