[master] 1f1234827 Use AM_SUBST_NOTMAKE directly

[Dridi Boukelmoune]

commit 1f1234827d315c6678c97d448253f53489367ae4
Author: Dridi Boukelmoune <dridi.boukelmoune at gmail.com>
Date:   Thu Feb 13 12:34:55 2020 +0100

    Use AM_SUBST_NOTMAKE directly
    
    I don't remember how I ended up with its private counterpart,
    conditionally even, but this has been part of automake since
    version 1.10 so there's no reason to beat around the bush.

diff --git a/varnish.m4 b/varnish.m4
index 13a273f39..a7ef062ab 100644
--- a/varnish.m4
+++ b/varnish.m4
@@ -226,8 +226,7 @@ clean-vmod-$1:
 "
 
 	AC_SUBST(m4_toupper(BUILD_VMOD_$1), [$VMOD_RULES])
-	m4_ifdef([_AM_SUBST_NOTMAKE],
-		[_AM_SUBST_NOTMAKE(m4_toupper(BUILD_VMOD_$1))])
+	AM_SUBST_NOTMAKE(m4_toupper(BUILD_VMOD_$1))
 ])
 
 # VARNISH_VMODS(NAMES)
@@ -418,8 +417,7 @@ clean-vsc-$1:
 "
 
 	AC_SUBST(m4_toupper(BUILD_VSC_$1), [$VSC_RULES])
-	m4_ifdef([_AM_SUBST_NOTMAKE],
-		[_AM_SUBST_NOTMAKE(m4_toupper(BUILD_VSC_$1))])
+	AM_SUBST_NOTMAKE(m4_toupper(BUILD_VSC_$1))
 ])
 
 # VARNISH_COUNTERS(NAMES)
@@ -488,8 +486,7 @@ clean-vut-$1:
 "
 
 	AC_SUBST(m4_toupper(GENERATE_$1_DOCS), [$VUT_RULES])
-	m4_ifdef([_AM_SUBST_NOTMAKE],
-		[_AM_SUBST_NOTMAKE(m4_toupper(GENERATE_$1_DOCS))])
+	AM_SUBST_NOTMAKE(m4_toupper(GENERATE_$1_DOCS))
 
 ])