MIPS: Rework GENERIC_HARDIRQS Kconfig.

Recent changes to CONFIG_GENERIC_HARDIRQS have caused us to start getting:

warning: (SMP && SYS_SUPPORTS_SMP) selects IRQ_PER_CPU which has unmet direct dependencies (HAVE_GENERIC_HARDIRQS)

Rearranging our Kconfig quiets the message.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
To: linux-mips@linux-mips.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Patchwork: https://patchwork.linux-mips.org/patch/1757/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/Kconfig

@@ -19,6 +19,8 @@ config MIPS
 	select GENERIC_ATOMIC64 if !64BIT
 	select HAVE_DMA_ATTRS
 	select HAVE_DMA_API_DEBUG
+	select HAVE_GENERIC_HARDIRQS
+	select GENERIC_IRQ_PROBE
 
 menu "Machine selection"
 
@@ -1921,20 +1923,6 @@ config CPU_R4000_WORKAROUNDS
 config CPU_R4400_WORKAROUNDS
 	bool
 
-#
-# Use the generic interrupt handling code in kernel/irq/:
-#
-config GENERIC_HARDIRQS
-	bool
-	default y
-
-config GENERIC_IRQ_PROBE
-	bool
-	default y
-
-config IRQ_PER_CPU
-	bool
-
 #
 # - Highmem only makes sense for the 32-bit kernel.
 # - The current highmem code will only work properly on physically indexed