PCI hotplug: remove redundant test in cpq hotplug

func is checked not to be NULL a few lines before.

A simplified version of the semantic patch that makes this change is as
follows: (http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r exists@
local idexpression x;
expression E;
position p1,p2;
@@

if (x@p1 == NULL || ...) { ... when forall
   return ...; }
... when != \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\|&x\)
(
x@p2 == NULL
|
x@p2 != NULL
)

// another path to the test that is not through p1?
@s exists@
local idexpression r.x;
position r.p1,r.p2;
@@

... when != x@p1
(
x@p2 == NULL
|
x@p2 != NULL
)

@fix depends on !s@
position r.p1,r.p2;
expression x,E;
statement S1,S2;
@@

(
- if ((x@p2 != NULL) || ...)
  S1
|
- if ((x@p2 == NULL) && ...) S1
|
- BUG_ON(x@p2 == NULL);
)
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

drivers/pci/hotplug/cpqphp_ctrl.c

@@ -1954,7 +1954,7 @@ void cpqhp_pushbutton_thread(unsigned long slot)
 			return ;
 		}
 
-		if (func != NULL && ctrl != NULL) {
+		if (ctrl != NULL) {
 			if (cpqhp_process_SI(ctrl, func) != 0) {
 				amber_LED_on(ctrl, hp_slot);
 				green_LED_off(ctrl, hp_slot);