libmisc: Move xmalloc.c to alloc.c

We'll expand the contents in a following commit, so let's move the file
to a more generic name, have a dedicated header, and update includes.

Signed-off-by: Alejandro Colomar <alx@kernel.org>

Use the new header for xstrdup()

Signed-off-by: Alejandro Colomar <alx@kernel.org>

libmisc/Makefile.am

@@ -10,6 +10,7 @@ libmisc_la_SOURCES = \
 	addgrps.c \
 	age.c \
 	agetpass.c \
+	alloc.c \
 	audit_help.c \
 	basename.c \
 	bit.c \
@@ -78,7 +79,6 @@ libmisc_la_SOURCES = \
 	xgetgrnam.c \
 	xgetgrgid.c \
 	xgetspnam.c \
-	xmalloc.c \
 	yesno.c
 
 if WITH_BTRFS

libmisc/copydir.c

@@ -17,6 +17,8 @@
 #include <sys/time.h>
 #include <fcntl.h>
 #include <stdio.h>
+
+#include "alloc.h"
 #include "prototypes.h"
 #include "defines.h"
 #ifdef WITH_SELINUX

libmisc/entry.c

@@ -13,6 +13,8 @@
 
 #include <sys/types.h>
 #include <stdio.h>
+
+#include "alloc.h"
 #include "prototypes.h"
 #include "defines.h"
 #include <pwd.h>

libmisc/env.c

@@ -15,6 +15,8 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+
+#include "alloc.h"
 #include "prototypes.h"
 #include "defines.h"
 #include "shadowlog.h"

libmisc/motd.c

@@ -12,9 +12,11 @@
 #ident "$Id$"
 
 #include <stdio.h>
-#include "prototypes.h"
+
+#include "alloc.h"
 #include "defines.h"
 #include "getdef.h"
+#include "prototypes.h"
 /*
  * motd -- output the /etc/motd file
  *