maint: remove dead store code and declarations

maint: remove dead store code and declarations

* libparted/labels/bsd.c (bsd_partition_set_flag): Remove dead store
and corresponding decl.
* libparted/arch/linux.c (init_ide): Likewise.
(_dm_maptype): Likewise.
(_mount_table_search): Likewise.
* libparted/fs/amiga/asfs.c (_asfs_probe): Likewise.
* libparted/labels/mac.c (mac_alloc_metadata): Likewise.
* libparted/labels/rdb.c (amiga_write): Likewise.
(amiga_write): Again.
* libparted/fs/amiga/apfs.c (_generic_apfs_probe): Likewise.
* libparted/fs/hfs/reloc_plus.c (hfsplus_effect_move_extent): Likewise.
* libparted/fs/hfs/reloc.c (hfs_effect_move_extent): Likewise.
* libparted/labels/dos.c (probe_partition_for_geom): Remove dead
store in "can't happen" case.