update/project/*: merge to update/project/trees

Just one script.

Just one!

Well, two, but the 2nd one already existed:
logic in update/project/trees and
update/project/repo was merged into
include/git.sh and update/project/build
was renamed to update/project/trees; an -f
option was added, which calls the functions
under git.sh

so git clones are now handled by the main build
script (for handling makefiles and defconfigs)
but the logic there is a stub, where git.sh
does all the actual heavy lifting

this cuts the file count down by two, and reduces
sloccount a reasonable amount because much of
the logic already exists in the build script, when
it comes to handling targets. git.sh was adjusted
to integrate with this, rather than act standalone

Signed-off-by: Leah Rowe <leah@libreboot.org>

script/update/vendor/inject

@@ -87,8 +87,8 @@ detect_board()
 
 build_dependencies()
 {
-	[ -d "${cbdir}" ] || x_ ./update project trees coreboot default
-	x_ ./update project build -b coreboot utils default
+	[ -d "${cbdir}" ] || x_ ./update project trees -f coreboot default
+	x_ ./update project trees -b coreboot utils default
 	x_ ./update vendor download ${board}
 }