ALSA: emu10k1: Load firmware when it was already cached

This expands the regression fix from
d2821599

.
The firmware also needs to be loaded when it was already cached.

Signed-off-by: Florian Zeitz <florob@babelmonkeys.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>