um: remove obsolete hw_interrupt_type

The defines and typedefs (hw_interrupt_type, no_irq_type, irq_desc_t) have
been kept around for migration reasons.  After more than two years it's
time to remove them finally.

This patch cleans up one of the remaining users.  When all such patches
hit mainline we can remove the defines and typedefs finally.

Impact: cleanup

Convert the last remaining users to struct irq_chip and remove the
define.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/um/kernel/irq.c

@@ -358,7 +358,7 @@ EXPORT_SYMBOL(um_request_irq);
 EXPORT_SYMBOL(reactivate_fd);
 
 /*
- * hw_interrupt_type must define (startup || enable) &&
+ * irq_chip must define (startup || enable) &&
  * (shutdown || disable) && end
  */
 static void dummy(unsigned int irq)
@@ -366,7 +366,7 @@ static void dummy(unsigned int irq)
 }
 
 /* This is used for everything else than the timer. */
-static struct hw_interrupt_type normal_irq_type = {
+static struct irq_chip normal_irq_type = {
 	.typename = "SIGIO",
 	.release = free_irq_by_irq_and_dev,
 	.disable = dummy,
@@ -375,7 +375,7 @@ static struct hw_interrupt_type normal_irq_type = {
 	.end = dummy
 };
 
-static struct hw_interrupt_type SIGVTALRM_irq_type = {
+static struct irq_chip SIGVTALRM_irq_type = {
 	.typename = "SIGVTALRM",
 	.release = free_irq_by_irq_and_dev,
 	.shutdown = dummy, /* never called */