docs: fb: Add TER16x32 to the available font names

The new font is available since recently.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>