PCI: pciehp: Drop unnecessary includes

Drop the following includes from pciehp source files which no longer use
any of the included symbols:

* <linux/sched/signal.h> in pciehp.h
  <linux/signal.h> in pciehp_hpc.c
  Added by commit de25968c ("fix more missing includes") to
  accommodate for a call to signal_pending().
  The call was removed by commit 262303fe ("pciehp: fix wait command
  completion").

* <linux/interrupt.h> in pciehp_core.c
  Added by historic commit f308a2df ("PCI: add PCI Express Port Bus
  Driver subsystem") to accommodate for a call to free_irq():
  https://git.kernel.org/tglx/history/c/f308a2dfbe63
  The call was removed by commit 407f452b ("pciehp: remove
  unnecessary free_irq").

* <linux/time.h> in pciehp_core.c and pciehp_hpc.c
  Added by commit 34d03419 ("PCIEHP: Add Electro Mechanical
  Interlock (EMI) support to the PCIE hotplug driver."),
  which was reverted by commit bd3d99c1 ("PCI: Remove untested
  Electromechanical Interlock (EMI) support in pciehp.").

* <linux/module.h> in pciehp_ctrl.c, pciehp_hpc.c and pciehp_pci.c
  Added by historic commit c16b4b14 ("PCI Hotplug: Add SHPC and PCI
  Express hot-plug drivers"):
  https://git.kernel.org/tglx/history/c/c16b4b14d980
  Module-related symbols were neither used back then in those files,
  nor are they used today.

* <linux/slab.h> in pciehp_ctrl.c
  Added by commit 5a0e3ad6 ("include cleanup: Update gfp.h and
  slab.h includes to prepare for breaking implicit slab.h inclusion from
  percpu.h") to accommodate for calls to kmalloc().
  The calls were removed by commit 0e94916e ("PCI: pciehp: Handle
  events synchronously").

* "../pci.h" in pciehp_ctrl.c
  Added by historic commit 67f4660b ("PCI: ASPM patch for") to
  accommodate for usage of the global variable pcie_mch_quirk:
  https://git.kernel.org/tglx/history/c/67f4660b72f2
  The global variable was removed by commit 0ba379ec ("PCI: Simplify
  hotplug mch quirk").
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

drivers/pci/hotplug/pciehp.h

@@ -19,7 +19,6 @@
 #include <linux/pci.h>
 #include <linux/pci_hotplug.h>
 #include <linux/delay.h>
-#include <linux/sched/signal.h>		/* signal_pending() */
 #include <linux/mutex.h>
 #include <linux/rwsem.h>
 #include <linux/workqueue.h>

drivers/pci/hotplug/pciehp_core.c

@@ -23,8 +23,6 @@
 #include <linux/types.h>
 #include <linux/pci.h>
 #include "pciehp.h"
-#include <linux/interrupt.h>
-#include <linux/time.h>
 
 #include "../pci.h"
 

drivers/pci/hotplug/pciehp_ctrl.c

@@ -13,13 +13,10 @@
  *
  */
 
-#include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/types.h>
-#include <linux/slab.h>
 #include <linux/pm_runtime.h>
 #include <linux/pci.h>
-#include "../pci.h"
 #include "pciehp.h"
 
 /* The following routines constitute the bulk of the

drivers/pci/hotplug/pciehp_hpc.c

@@ -13,15 +13,12 @@
  */
 
 #include <linux/kernel.h>
-#include <linux/module.h>
 #include <linux/types.h>
-#include <linux/signal.h>
 #include <linux/jiffies.h>
 #include <linux/kthread.h>
 #include <linux/pci.h>
 #include <linux/pm_runtime.h>
 #include <linux/interrupt.h>
-#include <linux/time.h>
 #include <linux/slab.h>
 
 #include "../pci.h"

drivers/pci/hotplug/pciehp_pci.c

@@ -13,7 +13,6 @@
  *
  */
 
-#include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/types.h>
 #include <linux/pci.h>