[PATCH] packagegroup: Make allarch inherit conditional

[Richard Purdie <richard.purdie@linuxfoundation.org>]

Make the allarch inherit conditional on PACKAGE_ARCH being left as
all. The one downside to this approach is that recipes need to set
PACKAGE_ARCH *before* inheriting the class in order to avoid the inherit.

The advantage is that we could start to detect the use of the
allarch inherit in the sstatesig code for improved task checksums.

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

diff --git a/meta/classes/packagegroup.bbclass b/meta/classes/packagegroup.bbclass
index 6606bc6..a79d5b05 100644
--- a/meta/classes/packagegroup.bbclass
+++ b/meta/classes/packagegroup.bbclass
@@ -9,7 +9,8 @@ PACKAGES = "${PN}"
 # By default, packagegroup packages do not depend on a certain architecture.
 # Only if dependencies are modified by MACHINE_FEATURES, packages
 # need to be set to MACHINE_ARCH after inheriting packagegroup.bbclass
-inherit allarch
+PACKAGE_ARCH ??= "all"
+inherit ${@oe.utils.ifelse(d.getVar('PACKAGE_ARCH', True) == 'all', 'allarch', '')}
 
 # This automatically adds -dbg and -dev flavours of all PACKAGES
 # to the list. Their dependencies (RRECOMMENDS) are handled as usual