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-sparc/prom.h b/include/asm-sparc/prom.h
index a8a121f..c755c69 100644
--- a/include/asm-sparc/prom.h
+++ b/include/asm-sparc/prom.h
@@ -23,6 +23,8 @@
 #define OF_ROOT_NODE_ADDR_CELLS_DEFAULT	2
 #define OF_ROOT_NODE_SIZE_CELLS_DEFAULT	1
 
+#define of_compat_cmp(s1, s2, l)	strncmp((s1), (s2), (l))
+
 typedef u32 phandle;
 typedef u32 ihandle;