[SH] Fix warnings about unhandled switch cases by adding defaults.

[Rot127]

#2010 (comment)

[XVilka]

A few still left:

 arch/SH/SHDisassembler.c: In function ‘op4xxb’:
arch/SH/SHDisassembler.c:960:33: warning: ‘rw’ may be used uninitialized [-Wmaybe-uninitialized]
  960 |                                 set_reg_n(info, SH_REG_R0, rw, rw, detail);
      |                                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/SH/SHDisassembler.c: In function ‘op4xx5’:
arch/SH/SHDisassembler.c:24:9: warning: ‘rw’ may be used uninitialized [-Wmaybe-uninitialized]
   24 |         switch(rw) {
      |         ^~~~~~
arch/SH/SHDisassembler.c:752:24: note: ‘rw’ was declared here
  752 |         enum direction rw;
      |                        ^~

https://github.com/capstone-engine/capstone/actions/runs/4962032517/jobs/8879573977?pr=2017#step:5:55

[Rot127]

Thanks. cmake and clangd did not catch this for whatever reason. Even with -Wmaybe-uninitialized added to compile options.

[XVilka]

All clear now.

[trufae]

Can we merge this so I can start testing from the next branch? Thanks @Rot127 ^_^

[XVilka]

@kabeor @aquynh

[kabeor]

Thanks, merged.