Makefile: Clarify/fix PDIR assignement

The previous version has this:
PDIR=$(subst /board/$(BOARD),,$(BDIR))

which is a little confusing as, when no public board overlay is set,
BDIR is only set to PBDIR _after_ this statement (but the logic
works as Makefile = recursively expands).

Also, this does not set PDIR correctly if both PBDIR and BDIR are
set (board overlay in both public and private).

It is much simpler to just use, as PBDIR is set correctly in both
cases, at that point in the function:
PDIR:=$(subst /board/$(BOARD),,$(PBDIR))

BRANCH=none
BUG=b:124804731
TEST=On m/master
     make buildall -j; mv build build.old
     After this CL:
     make buildall -j
     ls build/*/*/ec.*.smap | sed -e 's|build/||' | \
         xargs -I{} diff build/{} build.old/{}
     => no difference

Change-Id: I0a7a0c631b9b72dfcbf11d7cfd78bbaf3e21f1d5
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1485035
Reviewed-by: Yilun Lin <yllin@chromium.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/Makefile b/Makefile
index 716100fb88..ae3dc8c14a 100644
--- a/Makefile
+++ b/Makefile
@@ -31,7 +31,7 @@ ifneq (1,$(words $(PBDIR)))
 $(error multiple private definitions for BOARD $(BOARD): $(PBDIR))
 endif
 
-PDIR=$(subst /board/$(BOARD),,$(BDIR))
+PDIR:=$(subst /board/$(BOARD),,$(PBDIR))
 endif
 
 # If only private is present, use that as BDIR.