Add support for a saving build objects in a separate directory.
Modifications are based on the linux kernel approach and
support two use cases:
1) Add O= to the make command line
'make O=/tmp/build all'
2) Set environement variable BUILD_DIR to point to the desired location
'export BUILD_DIR=/tmp/build'
'make'
The second approach can also be used with a MAKEALL script
'export BUILD_DIR=/tmp/build'
'./MAKEALL'
Command line 'O=' setting overrides BUILD_DIR environent variable.
When none of the above methods is used the local build is performed and
the object files are placed in the source directory.
diff --git a/board/prodrive/pdnb3/config.mk b/board/prodrive/pdnb3/config.mk
index 6b0f18b..7670758 100644
--- a/board/prodrive/pdnb3/config.mk
+++ b/board/prodrive/pdnb3/config.mk
@@ -1,4 +1,4 @@
TEXT_BASE = 0x01f00000
# include NPE ethernet driver
-BOARDLIBS = cpu/ixp/npe/libnpe.a
+BOARDLIBS = $(obj)cpu/ixp/npe/libnpe.a