[POWERPC] Fix parse_drconf_memory() for 64-bit start addresses

Some new machines use the "ibm,dynamic-reconfiguration-memory" property
to provide memory layout information, rather than via memory nodes.

There is a bug in the code to parse this property for start addresses
over 4GB; we store the start address in an unsigned int, which means
we throw away the high bits and add apparently duplicate regions.
This results in a BUG() in free_bootmem_core().  This fixes it by
using an unsigned long instead.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index de45aa8..c12adc3dd 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -307,9 +307,9 @@
 	const unsigned int *lm, *dm, *aa;
 	unsigned int ls, ld, la;
 	unsigned int n, aam, aalen;
-	unsigned long lmb_size, size;
+	unsigned long lmb_size, size, start;
 	int nid, default_nid = 0;
-	unsigned int start, ai, flags;
+	unsigned int ai, flags;
 
 	lm = of_get_property(memory, "ibm,lmb-size", &ls);
 	dm = of_get_property(memory, "ibm,dynamic-memory", &ld);