Portability fixes:

- Use uid_t not __uid_t.
- Define _GNU_SOURCE for cpu_set_t and others.
- Include string.h for strncmp().
- Detect musl's ldd error message.

--- install/util.h	2014-10-24 13:19:58.000000000 +0200
+++ install/util.h	2014-12-28 07:58:51.723864634 +0100
@@ -20,6 +20,8 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
+#define _GNU_SOURCE
+
 #include <inttypes.h>
 #include <time.h>
 #include <sys/time.h>
@@ -27,6 +29,7 @@
 #include <stdbool.h>
 #include <stdlib.h>
 #include <stdio.h>
+#include <string.h>
 #include <signal.h>
 #include <sched.h>
 #include <limits.h>
--- install/dracut-install.c.orig	2014-10-24 13:19:58.000000000 +0200
+++ install/dracut-install.c	2014-12-30 10:16:25.850635694 +0100
@@ -222,7 +222,7 @@ static int cp(const char *src, const cha
                 if (ret == 0) {
                         struct timeval tv[2];
                         if (fchown(dest_desc, sb.st_uid, sb.st_gid) != 0)
-                                if(fchown(dest_desc, (__uid_t) - 1, sb.st_gid) != 0)
+                                if(fchown(dest_desc, (uid_t) - 1, sb.st_gid) != 0)
                                     log_error("Failed to chown %s: %m", dst);
                         tv[0].tv_sec = sb.st_atime;
                         tv[0].tv_usec = 0;
@@ -388,6 +388,11 @@ static int resolve_deps(const char *src)
                         break;
                 }
 
+		/* musl ldd */
+		if (strstr(buf, "Not a valid dynamic program"))
+			break;
+
+		/* glibc */
                 if (strstr(buf, "not a dynamic executable"))
                         break;