dev-lisp/c2ffi: style tweaks

- Put LLVM_MAX_SLOT before inherit so it's easier to spot
- Use ${LLVM_MAX_SLOT} rather than repeating 14 3 times

Signed-off-by: Sam James <sam@gentoo.org>

dev-lisp/c2ffi/c2ffi-14.0.0.20220729-r1.ebuild

@@ -3,6 +3,7 @@
 
 EAPI=8
 
+LLVM_MAX_SLOT=14
 inherit cmake llvm
 
 MY_COMMIT="25fcec13381f495460f4a4eafdd1b939c799df4a"
@@ -16,8 +17,6 @@ LICENSE="LGPL-2.1"
 SLOT="0"
 KEYWORDS="~amd64"
 
-LLVM_MAX_SLOT=14
-
-DEPEND="sys-devel/clang:14
-	sys-devel/llvm:14"
+DEPEND="sys-devel/clang:${LLVM_MAX_SLOT}
+	sys-devel/llvm:${LLVM_MAX_SLOT}"
 RDEPEND="${DEPEND}"