[yocto] COMPATIBLE_HOST in initramfs-live-install_1.0.bb

[Xu, Dongxiao]

Hi Tom,

I saw in initramfs-live-install_1.0.bb recipe, there is a line to set
the COMPATIBLE_HOST:

COMPATIBLE_HOST = "(i.86|x86_64).*-linux"

But actually initramfs-live-install is set as dependency in
core-image-minimal-initramfs.bb. Therefore if we set machine to be
"qemuarm" or something else that is not x86 architecture, and then
execute:
# bitbake core-image-minimal-initramfs
or
# bitbake universe

System will report an error of:

ERROR: Nothing RPROVIDES
'initramfs-live-install' (but /home/yocto-build5/poky-contrib/meta/recipes-core/images/core-image-minimal-initramfs.bb RDEPENDS on or otherwise requires it)
ERROR: initramfs-live-install was skipped: incompatible with host
arm-poky-linux-gnueabi (not in COMPATIBLE_HOST)
NOTE: Runtime target 'initramfs-live-install' is unbuildable,
removing...
Missing or unbuildable dependency chain was: ['initramfs-live-install']
ERROR: Required build target 'core-image-minimal-initramfs' has no
buildable providers.
Missing or unbuildable dependency chain was:
['core-image-minimal-initramfs', 'initramfs-live-install']

Summary: There was 1 WARNING message shown.
Summary: There were 2 ERROR messages shown, returning a non-zero exit
code.

Could you help to explain the background to set compatible host for the
initramfs-live-install recipe?

Thanks,
Dongxiao