Use safer allocation macros

Use of these macros, apart from the benefits mentioned in the commit
that adds the macros, has some other good side effects:

-  Consistency in getting the size of the object from sizeof(type),
   instead of a mix of sizeof(type) sometimes and sizeof(*p) other
   times.

-  More readable code: no casts, and no sizeof(), so also shorter lines
   that we don't need to cut.

-  Consistency in using array allocation calls for allocations of arrays
   of objects, even when the object size is 1.

Cc: Valentin V. Bartenev <vbartenev@gmail.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>

src/newusers.c

@@ -29,6 +29,8 @@
 #include <ctype.h>
 #include <errno.h>
 #include <string.h>
+
+#include "alloc.h"
 #ifdef ACCT_TOOLS_SETUID
 #ifdef USE_PAM
 #include "pam_defs.h"
@@ -1200,9 +1202,9 @@ int main (int argc, char **argv)
 #ifdef USE_PAM
 		/* keep the list of user/password for later update by PAM */
 		nusers++;
-		lines     = reallocf (lines,     nusers, sizeof (lines[0]));
-		usernames = reallocf (usernames, nusers, sizeof (usernames[0]));
-		passwords = reallocf (passwords, nusers, sizeof (passwords[0]));
+		lines     = REALLOCARRAYF(lines, nusers, int);
+		usernames = REALLOCARRAYF(usernames, nusers, char *);
+		passwords = REALLOCARRAYF(passwords, nusers, char *);
 		if (lines == NULL || usernames == NULL || passwords == NULL) {
 			fprintf (stderr,
 			         _("%s: line %d: %s\n"),