emit_local(): Fix unused warning

emit_local(): Fix unused warning

Honzas r221269 produced

gcc/varasm.c:1936:7: error: unused variable ‘align’
[-Werror=unused-variable]
   int align = symtab_node::get (decl)->definition_alignment ();
       ^
on e.g.:

log/alpha64-dec-vms
log/alpha-dec-vms
log/i686-cygwinOPT-enable-threads=yes
log/i686-mingw32crt
log/i686-openbsd3.0
log/i686-pc-msdosdjgpp
log/m68k-openbsd

Silence this by moving the variable into the corresponding blocks and
adding back the ATTRIBUTE_UNUSED decoration for the decl param.

From-SVN: r221925