drm/i915: Uncomment the use of hex_dump_to_buffer() [FreeBSD]

It is implemented in FreeBSD as of ...

Sponsored by:	The FreeBSD Foundation

Author: dumbbell

drivers/gpu/drm/i915/gt/intel_engine_cs.c

@@ -2090,12 +2090,10 @@ static void linux_hexdump(struct drm_printer *m, const void *buf, size_t len)
 			continue;
 		}
 
-#ifdef __linux__
 		WARN_ON_ONCE(hex_dump_to_buffer(buf + pos, len - pos,
 						rowsize, sizeof(u32),
 						line, sizeof(line),
 						false) >= sizeof(line));
-#endif
 		drm_printf(m, "[%04zx] %s\n", pos, line);
 
 		prev = buf + pos;