Staging: rtl8192e: remove another firmware header file not being used

The built-in firmware images are never used, the firmware files
are downloaded to the device through the standard firmware interface.

This removes the firmware header file as it's not ever used.
It also removes a .h file as it is not needed.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --cc drivers/staging/rtl8192e/r819xE_firmware.c
Simple merge

diff --cc drivers/staging/rtl8192e/r819xE_firmware.h
Simple merge

diff --cc drivers/staging/rtl8192e/r819xE_firmware_img.h
Simple merge