[OE-core] gcc 4.6 recipes naming

[Khem Raj]

Hi

I have gcc 4.6 under progress here. As we know the current release is
4.6.0. I have been calling the recipes
to omit the minor release number so the recipes are called
<recipes>_4.6.bb based on my experiences
with gcc releases over the years.

Since the minor releases are bug fix releases and when next bug fix
release happens the total diff
of changes from 4.6.0 to 4.6.1 are also released as a single diff
which can be applied on top of existing
4.6.0 tar file to reach 4.6.1

This makes the upgrade easier for minor releases. I decided not to
track the release branch since
that complicates the gcc download as in classic oe

So for upgrades we can either just take the diff from 4.6.0 to 4.6.1
and apply on top of 4.6.0 or
decide to use the new 4.6.1 tar both would be ok as we decide that later.

Let me know your thoughts.

-Khem