Replace non-portable asprintf by g_strdup_printf

g_strdup_printf already handles OOM errors, so some error handling in
QEMU code can be removed.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
diff --git a/exec.c b/exec.c
index 5689613..b85508b 100644
--- a/exec.c
+++ b/exec.c
@@ -863,18 +863,16 @@
         return NULL;
     }
 
-    if (asprintf(&filename, "%s/qemu_back_mem.XXXXXX", path) == -1) {
-        return NULL;
-    }
+    filename = g_strdup_printf("%s/qemu_back_mem.XXXXXX", path);
 
     fd = mkstemp(filename);
     if (fd < 0) {
         perror("unable to create backing store for hugepages");
-        free(filename);
+        g_free(filename);
         return NULL;
     }
     unlink(filename);
-    free(filename);
+    g_free(filename);
 
     memory = (memory+hpagesize-1) & ~(hpagesize-1);