greybus: update sysfs documentation files

Impose a few editorial conventions on the Greybus-related sysfs
files under "Documentation".
    - Capitalize "Endo" (except in path names)
    - Capitalize "ID" (except in path names)
    - Use "..." to indicate unspecified path components (because
      ".." means something else).
    - Add the "0x" prior to the "XXXX" representing the Endo ID.
Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/staging/greybus/Documentation/sysfs-bus-greybus

-What:		/sys/bus/greybus/device/endo-XXXX
+What:		/sys/bus/greybus/device/endo-0xXXXX
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
@@ -7,7 +7,7 @@ Description:
 		replaced with the numeric value of the endo layout
 		scheme as documented in the ARA Module Developer Kit.
 
-What:		/sys/bus/greybus/device/endo-XXXX/Endo/id
+What:		/sys/bus/greybus/device/endo-0xXXXX/Endo/id
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
@@ -16,7 +16,7 @@ Description:
 		defined by the the Endo layout scheme, documented in
 		the ARA Module Developer Kit.
 
-What:		/sys/bus/greybus/device/endo-XXXX/Endo/ap_intf_id
+What:		/sys/bus/greybus/device/endo-0xXXXX/Endo/ap_intf_id
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
@@ -26,21 +26,21 @@ Description:
 		The interface positions are defined in the ARA
 		Module Developer Kit.
 
-What:		/sys/bus/greybus/device/endo-XXXX/SVC/serial_number
+What:		/sys/bus/greybus/device/endo-0xXXXX/SVC/serial_number
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
 		The serial number of the SVC device
 
-What:		/sys/bus/greybus/device/endo-XXXX/SVC/version
+What:		/sys/bus/greybus/device/endo-0xXXXX/SVC/version
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
 		The version number of the firmware in the SVC device.
 
-What:		/sys/bus/greybus/device/endo-XXXX/../epm
+What:		/sys/bus/greybus/device/endo-0xXXXX/.../epm
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
@@ -50,7 +50,7 @@ Description:
 		Writing 1 to it turns it on, writing 0 to it turns it
 		off.  Reading the value returns if it is on or off.
 
-What:		/sys/bus/greybus/device/endo-XXXX/../power_control
+What:		/sys/bus/greybus/device/endo-0xXXXX/.../power_control
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
@@ -60,7 +60,7 @@ Description:
 		to the module, writing 0 to it turns power off to the
 		module.  Reading the value returns if it is on or off.
 
-What:		/sys/bus/greybus/device/endo-XXXX/../present
+What:		/sys/bus/greybus/device/endo-0xXXXX/.../present
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
@@ -124,14 +124,14 @@ Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
-		The protocol id of a Greybus connection.
+		The protocol ID of a Greybus connection.
 
 What:		/sys/bus/greybus/device/.../device_id
 Date:		October 2015
 KernelVersion:	4.XX
 Contact:	Greg Kroah-Hartman <greg@kroah.com>
 Description:
-		The device id of a Greybus bundle.
+		The device ID of a Greybus bundle.
 
 What:		/sys/bus/greybus/device/.../state
 Date:		October 2015