zephyr-philosophers: use ZEPHYR_GCC_VARIANT="yocto"

Setting ZEPHYR_GCC_VARIANT="yocto" will result in images being
built by our own Makefile: Makefile.toolchain.yocto
The Makefile already contains LIB_INCLUDE_DIR definition, so it
can be removed from this recipe.

Signed-off-by: Juro Bystricky <juro.bystricky@intel.com>

recipes-kernel/zephyr-kernel/zephyr-philosophers.bb

@@ -6,8 +6,6 @@ INHIBIT_DEFAULT_DEPS = "1"
 
 DEPENDS += "gcc-cross-${TARGET_ARCH} libgcc"
 
-export ZEPHYR_GCC_VARIANT="zephyr"
-
 # The makefiles are explicit about the flags they want, so don't unset
 # them so zephyr flags actually get used.
 # This is done here rather than in the task so that things still work
@@ -20,16 +18,17 @@ python () {
 
 do_configure[noexec] = "1"
 
-LIB_INCLUDE_DIR="-L`dirname \`$CC -print-libgcc-file-name\``"
 CROSS_COMPILE="${STAGING_BINDIR_TOOLCHAIN}/${TARGET_PREFIX}"
 
 # oe_runmake isn't used because of the make -e causing issues with some
 # make variables.
-MAKE_COMMAND = "make -j V=1 BOARD=${BOARD} CROSS_COMPILE=${CROSS_COMPILE} LIB_INCLUDE_DIR=${LIB_INCLUDE_DIR}"
+
+MAKE_COMMAND = "make -j V=1 BOARD=${BOARD} CROSS_COMPILE=${CROSS_COMPILE}"
 
 do_compile () {
     cd ${S}
     export ZEPHYR_BASE=${S}
+    export ZEPHYR_GCC_VARIANT="yocto"
     ${MAKE_COMMAND} -C samples/philosophers pristine
     ${MAKE_COMMAND} -C samples/philosophers
 }