usb: gadget: configfs: Ignore trailing LF for user strings to cdev

usb: gadget: configfs: Ignore trailing LF for user strings to cdev

Since commit c033563220e0f7a8
("usb: gadget: configfs: Attach arbitrary strings to cdev")
a user can provide extra string descriptors to a USB gadget via configfs.

For "manufacturer", "product", "serialnumber", setting the string via
configfs ignores a trailing LF.

For the arbitrary strings the LF was not ignored.

This patch ignores a trailing LF to make this consistent with the existing
behavior for "manufacturer", ...  string descriptors.

Fixes: c033563220e0 ("usb: gadget: configfs: Attach arbitrary strings to cdev")
Cc: stable <stable@kernel.org>
Signed-off-by: Ingo Rohloff <ingo.rohloff@lauterbach.com>
Link: https://lore.kernel.org/r/20241212154114.29295-1-ingo.rohloff@lauterbach.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>