Move our local m4 macros to gl/m4

The gl subdirectory contains our local versions of gnulib module
implementations, so move m4/acinclude.m4 and m4/dospaths.m4 there.

* gl/modules/make-macros: Create a new module to handle the macros.
* bootstrap.conf: Add the new module.
* configure.ac: Macro invocation is moved to make-macros.
* m4/.gitignore: Delete unnecessary ignore file: m4 is empty.
* .gitignore: Add m4/ as an ignored directory.

.gitignore

@@ -18,6 +18,7 @@ GTAGS
 
 # Configure artifacts
 /lib/
+/m4/
 ABOUT-NLS
 INSTALL
 Makefile

bootstrap.conf

@@ -57,4 +57,5 @@ fdl
 findprog-in
 getloadavg
 host-cpu-c-abi
-make-glob"
+make-glob
+make-macros"

configure.ac

@@ -110,9 +110,6 @@ AS_IF([test "$make_cv_file_timestamp_hi_res" = yes],
   ])
 ])
 
-# Check for DOS-style pathnames.
-pds_AC_DOS_PATHS
-
 # See if we have a standard version of gettimeofday().  Since actual
 # implementations can differ, just make sure we have the most common
 # one.

gl/modules/make-macros

@@ -0,0 +1,16 @@
+Description:
+Install m4 macros for GNU make.
+
+Files:
+m4/acinclude.m4
+m4/dospaths.m4
+
+configure.ac:
+# Check for DOS-style pathnames.
+pds_AC_DOS_PATHS
+
+License:
+GPLv3+
+
+Maintainer:
+gnumake

m4/.gitignore

@@ -1,5 +0,0 @@
-*
-!/.gitignore
-!/aclocal.m4
-!/dospaths.m4
-