microblaze: Add PVR for BTC

Signed-off-by: Michal Simek <monstr@monstr.eu>

arch/microblaze/include/asm/pvr.h

@@ -30,7 +30,8 @@ struct pvr_s {
 #define PVR0_USE_EXC_MASK		0x04000000
 #define PVR0_USE_ICACHE_MASK		0x02000000
 #define PVR0_USE_DCACHE_MASK		0x01000000
-#define PVR0_USE_MMU			0x00800000	/* new */
+#define PVR0_USE_MMU			0x00800000
+#define PVR0_USE_BTC			0x00400000
 #define PVR0_VERSION_MASK		0x0000FF00
 #define PVR0_USER1_MASK			0x000000FF