powerpc/irq: Add helper to set regs->softe

regs->softe doesn't exist on PPC32.

Add irq_soft_mask_regs_set_state() helper to set regs->softe.
This helper will void on PPC32.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/5f37d1177a751fdbca79df461d283850ca3a34a2.1612796617.git.christophe.leroy@csgroup.eu

arch/powerpc/include/asm/hw_irq.h

@@ -38,6 +38,8 @@
 #define PACA_IRQ_MUST_HARD_MASK	(PACA_IRQ_EE)
 #endif
 
+#endif /* CONFIG_PPC64 */
+
 /*
  * flags for paca->irq_soft_mask
  */
@@ -46,8 +48,6 @@
 #define IRQS_PMI_DISABLED	2
 #define IRQS_ALL_DISABLED	(IRQS_DISABLED | IRQS_PMI_DISABLED)
 
-#endif /* CONFIG_PPC64 */
-
 #ifndef __ASSEMBLY__
 
 #ifdef CONFIG_PPC64
@@ -287,6 +287,10 @@ extern void irq_set_pending_from_srr1(unsigned long srr1);
 
 extern void force_external_irq_replay(void);
 
+static inline void irq_soft_mask_regs_set_state(struct pt_regs *regs, unsigned long val)
+{
+	regs->softe = val;
+}
 #else /* CONFIG_PPC64 */
 
 static inline unsigned long arch_local_save_flags(void)
@@ -355,6 +359,9 @@ static inline bool arch_irq_disabled_regs(struct pt_regs *regs)
 
 static inline void may_hard_irq_enable(void) { }
 
+static inline void irq_soft_mask_regs_set_state(struct pt_regs *regs, unsigned long val)
+{
+}
 #endif /* CONFIG_PPC64 */
 
 #define ARCH_IRQ_INIT_FLAGS	IRQ_NOREQUEST