generic packages: use $(HOST_DIR) instead of $(HOST_DIR)/usr as prefix

Remove the redundant usr/ component of the HOST_DIR paths. Since a
previous commit added a symlink from $(HOST_DIR)/usr to $(HOST_DIR),
everything keeps on working.

This is a mechanical change with
git grep -l '\$(HOST_DIR)/usr' | xargs sed -i 's%\(prefix\|PREFIX\)=\("\?\)\$(HOST_DIR)/usr%\1=\2$(HOST_DIR)%g'

Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/cmake/cmake.mk

@@ -41,7 +41,7 @@ define HOST_CMAKE_CONFIGURE_CMDS
 	(cd $(@D); \
 		$(HOST_CONFIGURE_OPTS) \
 		CFLAGS="$(HOST_CMAKE_CFLAGS)" \
-		./bootstrap --prefix=$(HOST_DIR)/usr \
+		./bootstrap --prefix=$(HOST_DIR) \
 			--parallel=$(PARALLEL_JOBS) -- \
 			-DCMAKE_C_FLAGS="$(HOST_CMAKE_CFLAGS)" \
 			-DCMAKE_CXX_FLAGS="$(HOST_CMAKE_CXXFLAGS)" \