PCI / PM: Fix small typo in documentation

cuased -> caused

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/Documentation/power/pci.txt b/Documentation/power/pci.txt
index b0e911e..4455888 100644
--- a/Documentation/power/pci.txt
+++ b/Documentation/power/pci.txt
@@ -999,7 +999,7 @@
 
 It is important to remember that the driver's runtime_suspend() callback
 may be executed right after the usage counter has been decremented, because
-user space may already have cuased the pm_runtime_allow() helper function
+user space may already have caused the pm_runtime_allow() helper function
 unblocking the runtime PM of the device to run via sysfs, so the driver must
 be prepared to cope with that.