Set the baseband_usb_chr driver as build-in and modify it for modem image downloading.

1. Add TCGETS in baseband_usb_chr_ioctl.

2. Remove the queue cycle of baseband_usb_chr_work, and add queue_work when the device has been probed.
   This will avoid that the delay in baseband_usb_chr_work cause the devices cannot be found by controller.

3. Init the usb of baseband_usb_chr while baseband_usb_driver_disconnect() is invoked to avoid the kernel panic.

4. Return in the complete function of urb submition when urb->status is error code.
   This can avoid infinite loop when error occurs for urb submition.

5. Add log tag "CHR" if debug is enabled.

Change-Id: Id1a08afb9a56f62193bc80158f4b43e28b714814

Conflicts:
	arch/arm/configs/tegra3_android_defconfig
	drivers/usb/serial/baseband_usb_chr.c