xen/decompress: Drop bool_t and use bool instead

In particular, the libxg wrapper for unxz.c uses char for bool_t which is a
major antipattern.  Luckily the code doesn't suffer from truncated values.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>

tools/libs/guest/xg_dom_decompress_unsafe_xz.c

@@ -11,7 +11,6 @@
 // TODO
 #define XZ_DEC_X86
 
-typedef char bool_t;
 typedef uint8_t u8;
 typedef uint16_t u16;
 typedef uint32_t u32;