Fix build for (at least) older NetBSD versions that do not have
execvpe(3).

Index: Makefile
===================================================================
RCS file: /cvsroot/pkgsrc/print/cups-filters/Makefile,v
retrieving revision 1.56
diff -u -p -r1.56 Makefile
--- Makefile	1 Nov 2016 08:20:17 -0000	1.56
+++ Makefile	2 Nov 2016 15:04:54 -0000
@@ -1,7 +1,7 @@
 # $NetBSD: Makefile,v 1.56 2016/11/01 08:20:17 leot Exp $
 
 DISTNAME=	cups-filters-1.11.5
-PKGREVISION=	1
+PKGREVISION=	2
 CATEGORIES=	print
 MASTER_SITES=	http://openprinting.org/download/cups-filters/
 EXTRACT_SUFX=	.tar.xz
Index: distinfo
===================================================================
RCS file: /cvsroot/pkgsrc/print/cups-filters/distinfo,v
retrieving revision 1.40
diff -u -p -r1.40 distinfo
--- distinfo	31 Oct 2016 09:31:16 -0000	1.40
+++ distinfo	2 Nov 2016 15:04:54 -0000
@@ -4,3 +4,5 @@ SHA1 (cups-filters-1.11.5.tar.xz) = a377
 RMD160 (cups-filters-1.11.5.tar.xz) = 1ee7650499ce8eacf6093a753e2512433d4c2033
 SHA512 (cups-filters-1.11.5.tar.xz) = 8c837ff4f7c9b9abdf7f6f0ff899aa60444a73934e7e41d0b840a865d44650090b2d00b8a211ea2618a94dd8c1506a83061e6de0fe03947a3aee0e8425349e4f
 Size (cups-filters-1.11.5.tar.xz) = 1409912 bytes
+SHA1 (patch-filter_gstoraster.c) = a9fac7892972943f345c6b76529feff0ba098458
+SHA1 (patch-filter_mupdftoraster.c) = 4c4f7d292163657f9541c8ce454ba57d248f7ef0
Index: patches/patch-filter_gstoraster.c
===================================================================
RCS file: patches/patch-filter_gstoraster.c
diff -N patches/patch-filter_gstoraster.c
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ patches/patch-filter_gstoraster.c	2 Nov 2016 15:04:54 -0000
@@ -0,0 +1,16 @@
+$NetBSD$
+
+execvpe(3) appeared only on NetBSD 8.0, use execve(3) instead (like
+cups-filters-1.11.4).
+
+--- filter/gstoraster.c.orig	2016-10-27 22:50:52.000000000 +0000
++++ filter/gstoraster.c
+@@ -502,7 +502,7 @@ gs_spawn (const char *filename,
+     }
+ 
+     /* Execute Ghostscript command line ... */
+-    execvpe(filename, gsargv, envp);
++    execve(filename, gsargv, envp);
+     perror(filename);
+     goto out;
+   }
Index: patches/patch-filter_mupdftoraster.c
===================================================================
RCS file: patches/patch-filter_mupdftoraster.c
diff -N patches/patch-filter_mupdftoraster.c
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ patches/patch-filter_mupdftoraster.c	2 Nov 2016 15:04:54 -0000
@@ -0,0 +1,16 @@
+$NetBSD$
+
+execvpe(3) appeared only on NetBSD 8.0, use execve(3) instead (like
+cups-filters-1.11.4).
+
+--- filter/mupdftoraster.c.orig	2016-10-27 22:50:52.000000000 +0000
++++ filter/mupdftoraster.c
+@@ -215,7 +215,7 @@ mutool_spawn (const char *filename,
+ 
+   if ((pid = fork()) == 0) {
+     /* Execute Mutool command line ... */
+-    execvpe(filename, mutoolargv, envp);
++    execve(filename, mutoolargv, envp);
+     perror(filename);
+     goto out;
+   }