[SCSI] aic7xxx: fix aicasm build failure with gcc-3.4.6

On Tue, 2007-05-22 at 06:51 -0500, Bob Tracy wrote:
> Second try: originally reported this back on April 17th.  2.6.X
> kernel builds started failing after I upgraded my compiler from
> gcc-3.3.X to gcc-3.4.6:
>
> make -C drivers/scsi/aic7xxx/aicasm
> (...)
> gcc -I/usr/include -I. aicasm.c aicasm_symbol.c aicasm_gram.c aicasm_macro_gram.c aicasm_scan.c aicasm_macro_scan.c -o aicasm -ldb
> aicasm_gram.y:1948: error: conflicting types for 'yyerror'
> aicasm_gram.tab.c:3004: error: previous implicit declaration of 'yyerror' was here
> aicasm_macro_gram.y:162: error: conflicting types for 'mmerror'
> aicasm_macro_gram.tab.c:1196: error: previous implicit declaration of 'mmerror' was here

Fix is to add a prototype for yyerror and mmerror to the relevant files.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>