powerpc: On POWERNV enable PPC_DENORMALISATION by default

We want PPC_DENORMALISATION enabled when POWERNV is enabled,
so update the Kconfig.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: <stable@vger.kernel.org>
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 3bf72cd..dbd9d3c 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -566,7 +566,7 @@
 config PPC_DENORMALISATION
 	bool "PowerPC denormalisation exception handling"
 	depends on PPC_BOOK3S_64
-	default "n"
+	default "y" if PPC_POWERNV
 	---help---
 	  Add support for handling denormalisation of single precision
 	  values.  Useful for bare metal only.  If unsure say Y here.