ALSA: es18xx: code improvements

1. Set the third argument of the snd_device_new to not NULL, so there is
   no warning about bug during chip detection. The third argument is not
   used in this driver. It was changed in my previous patch.

2. Remove the fm_port and mpu_port fields from the snd_es18xx structure.
   They can be converted to function arguments.

3. Remove the dmaN_size fields from the snd_es18xx structure. These
   values are used only in pointer functions and can be easily calculated.

4. Remove the ctrl_lock spinlock which is used only in one read function
   which is called once during chip initialization. There are many
   writes to the same register and they are not protected on purpose
   (see the comment ina the snd_es18xx_config_write()).

5. Use the first part of the text5Sources string table as the text4Soruces
   table (they are the same).

6. Merge the same cases for the ES1887 and ES1888 when setting chip's caps.

7. Move the snd_es18xx_reset() to __devinit section.

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Takashi Iwai <tiwai@suse.de>