SB16 build error.

[Ralf Baechle <ralf@linux-mips.org>]

Found on a MIPS build but certain other architectures will have the same
issue:

  CC      sound/isa/sb/sb16_csp.o
sound/isa/sb/sb16_csp.c: In function ‘snd_sb_csp_ioctl’:
sound/isa/sb/sb16_csp.c:228: error: case label does not reduce to an integer 
constant
make[1]: *** [sound/isa/sb/sb16_csp.o] Error 1
make: *** [sound/isa/sb/sb16_csp.o] Error 2

This error message is caused by the _IOC_TYPECHECK() error check triggering
due to excessive ioctl size on Alpha, PowerPC, MIPS and SPARC which define
_IOC_SIZEBITS as 13.  On all other architectures define it as 14 so struct
snd_sb_csp_microcode with it's little over 12kB will just about fit into
the 16kB limit.

  Ralf