YAMAMOTO Takashi aa8aadf18e Use "uname -s" where "uname -o" is not available ...

Namely this changes HOSTOS for macOS from "Other" to "Darwin".

Also, suppress the following harmless messages during a "make":
(Missing redirect in tools/Makefile.host)

	uname: illegal option -- o
	usage: uname [-amnprsv]

2020-01-29 09:03:48 +01:00

..

qemu

Use "uname -s" where "uname -o" is not available

2020-01-29 09:03:48 +01:00