[sparc64] Fix build of graphics/mojoshader

[Kurt Mosiejczuk]

graphics/mojoshader needs ports-gcc on sparc64.

ok?

(cc MAINTAINER)

--Kurt

Index: Makefile
===================================================================
RCS file: /cvs/ports/graphics/mojoshader/Makefile,v
retrieving revision 1.12
diff -u -p -r1.12 Makefile
--- Makefile    12 Dec 2021 04:41:03 -0000      1.12
+++ Makefile    5 Jan 2022 07:21:08 -0000
@@ -18,6 +18,9 @@ HOMEPAGE =    https://icculus.org/mojoshade
 # zlib
 PERMIT_PACKAGE =       Yes
 
+COMPILER =     base-clang ports-gcc
+COMPILER_LANGS =       c
+
 WANTLIB += m
 
 MODULES =      devel/cmake