app-crypt/coolkey: fix build w/ upcoming clang16

Header that declare this is not installed, and seems like these
headers would conflict in all sorts of ways here either way.

An alternative fix could be to drop --enable-pk11install which is
marked legacy (off by default), but don't know this package and
no idea if anyone need this.

Closes: https://bugs.gentoo.org/871585
Signed-off-by: Ionen Wolkens <ionen@gentoo.org>

app-crypt/coolkey/coolkey-1.1.0-r9.ebuild

@@ -1,4 +1,4 @@
-# Copyright 1999-2021 Gentoo Authors
+# Copyright 1999-2022 Gentoo Authors
 # Distributed under the terms of the GNU General Public License v2
 
 EAPI=7
@@ -26,6 +26,7 @@ BDEPEND="virtual/pkgconfig"
 
 PATCHES=(
 	"${WORKDIR}/${PN}-patches"
+	"${FILESDIR}/${P}-clang16.patch"
 )
 
 pkg_setup() {

app-crypt/coolkey/files/coolkey-1.1.0-clang16.patch

@@ -0,0 +1,13 @@
+Declaration taken from nss sources' lib/softoken/pkcs11i.h.
+Only needed with --enable-pk11install.
+
+https://bugs.gentoo.org/871585
+--- a/src/install/pk11install.c
++++ b/src/install/pk11install.c
+@@ -23,4 +23,6 @@
+ #include "pkcs11n.h"
+ 
++char **NSC_ModuleDBFunc(unsigned long function, char *parameters, void *args);
++
+ /*
+  * windows specific globing search