device_tree: Fix a typo

Fix spelling of 'allocting' -> 'allocating'.

Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>

device_tree.c

@@ -241,7 +241,7 @@ uint32_t qemu_fdt_alloc_phandle(void *fdt)
 
     /*
      * We need to find out if the user gave us special instruction at
-     * which phandle id to start allocting phandles.
+     * which phandle id to start allocating phandles.
      */
     if (!phandle) {
         phandle = machine_phandle_start(current_machine);