cmake: respect ${S} and ${B}

Instead of the class-specific variables OECMAKE_BUILDPATH and
OECMAKE_SOURCEPATH, just use ${B} and ${S}.

If these two paths are different, delete any existing ${B} before running a
build so that previous builds don't taint the current build.

Note that OECMAKE_SOURCEPATH and OECMAKE_BUILDPATH are not respected, so recipes
that manually set these in the past will need to be updated to either use
something along the lines of separatebuilddir.inc or set B themselves.  If the
old variables are set, a warning is displayed.

Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>

0 files changed, 0 insertions, 0 deletions