multilib.conf: conditionalize MULTILIB_GLOBAL_VARIANTS

The actual use case may have been a little unusual, but I ended up with a machine's .conf file specifying arch-specific MULTILIB_GLOBAL_VARIANTS, and having it not work. On study, I found that multilib.conf was getting read after that.

And I think this ought to work more like DEFAULTTUNE, where the idiom is:
DEFAULTTUNE = "something"
require some/tune.inc

and similarly, I think it would make sense to allow:
MULTILIB_GLOBAL_VARIANTS = "list of variants" require multilib.conf

The following changes since commit 97756472d3a69eaca95d105494ffea78c6b077e0:

build-appliance-image: Update to dizzy head revision (2014-10-18 16:16:27 +0200)

are available in the git repository at:
git://git.yoctoproject.org/poky-contrib seebs/multilib_global_variants
http://git.yoctoproject.org/cgit.cgi/poky-contrib/log/?h=seebs/multilib_global_variants

Peter Seebach (1):
multilib.conf: set MULTILIB_GLOBAL_VARIANTS conditionally

 meta/conf/multilib.conf |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

It is not entirely obvious that all reasonable configurations will have multilib.conf strictly before the file which might want to set MULTILIB_GLOBAL_VARIANTS. The x86-ish values here look like reasonable default guesses, but shouldn't override an explicit setting.

---
 meta/conf/multilib.conf |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

index 733236d..37e8481 100644
@@ -14,6 +14,6 @@ INHERIT += "multilib_global"
 
 BBCLASSEXTEND_append = " ${MULTILIBS}"
 
-MULTILIB_GLOBAL_VARIANTS  = "lib32 lib64 libx32"
+MULTILIB_GLOBAL_VARIANTS ?= "lib32 lib64 libx32"
 
 OPKG_ARGS_append = " --force-maintainer --force-overwrite"

1.7.1