Consolidate of_device_is_compatible

The only difference here is that Sparc uses strncmp to match compatibility
names while PowerPC uses strncasecmp.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Paul Mackerras <paulus@samba.org>
Acked-by: David S. Miller <davem@davemloft.net>
diff --git a/include/asm-powerpc/prom.h b/include/asm-powerpc/prom.h
index 9fe0152..b05f8f2 100644
--- a/include/asm-powerpc/prom.h
+++ b/include/asm-powerpc/prom.h
@@ -24,6 +24,8 @@
 #define OF_ROOT_NODE_ADDR_CELLS_DEFAULT	1
 #define OF_ROOT_NODE_SIZE_CELLS_DEFAULT	1
 
+#define of_compat_cmp(s1, s2, l)	strncasecmp((s1), (s2), (l))
+
 /* Definitions used by the flattened device tree */
 #define OF_DT_HEADER		0xd00dfeed	/* marker */
 #define OF_DT_BEGIN_NODE	0x1		/* Start of node, full name */