[POWERPC] Rename MPIC_BROKEN_U3 to MPIC_U3_HT_IRQS

Rename MPIC_BROKEN_U3 to something a little more descriptive. Its
effect is to enable support for HT irqs behind the PCI-X/HT bridge on
U3/U4 (aka. CPC9x5) parts.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/platforms/maple/Kconfig b/arch/powerpc/platforms/maple/Kconfig
index 5f364b8..f7c95eb 100644
--- a/arch/powerpc/platforms/maple/Kconfig
+++ b/arch/powerpc/platforms/maple/Kconfig
@@ -3,7 +3,7 @@
 	bool "Maple 970FX Evaluation Board"
 	select MPIC
 	select U3_DART
-	select MPIC_BROKEN_U3
+	select MPIC_U3_HT_IRQS
 	select GENERIC_TBSYNC
 	select PPC_UDBG_16550
 	select PPC_970_NAP