sci-libs/mc: update EAPI 7 -> 8, port to C99

Missing function declaration. Builds with -std=gnu23 on gcc-14

Closes: https://bugs.gentoo.org/886457
Signed-off-by: NHOrus <jy6x2b32pie9@yahoo.com>
Closes: https://github.com/gentoo/gentoo/pull/40332
Signed-off-by: Sam James <sam@gentoo.org>

sci-libs/mc/files/mc-1.5-missing-decl.patch

@@ -0,0 +1,13 @@
+Fix missing function declaration, so package could build with modern compilers
+https://bugs.gentoo.org/886457
+--- a/src/aprx/estim.c
++++ b/src/aprx/estim.c
+@@ -41,6 +41,8 @@
+     Bvec *u, Bvec *ud, Bvec *r);
+ VEXTERNC void Aprx_estFaceBump(Aprx *thee, int color,
+     Bvec *u, Bvec *ud, Bvec *r);
++VPUBLIC int Aprx_markRefineDorfler (Aprx *thee, double percentToRefine,
++    int color);
+ 
+ /*
+  * ***************************************************************************

sci-libs/mc/mc-1.5-r1.ebuild

@@ -1,7 +1,7 @@
-# Copyright 1999-2024 Gentoo Authors
+# Copyright 1999-2025 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
-EAPI=7
+EAPI=8
 
 inherit autotools fortran-2
 
@@ -38,6 +38,7 @@ PATCHES=(
 	"${FILESDIR}"/1.4-multilib.patch
 	"${FILESDIR}"/1.4-doc.patch
 	"${FILESDIR}"/${P}-unbundle.patch
+	"${FILESDIR}"/${P}-missing-decl.patch
 )
 
 src_prepare() {