Replace calls to strbuf_init(&foo, 0) with STRBUF_INIT initializer

Many call sites use strbuf_init(&foo, 0) to initialize local
strbuf variable "foo" which has not been accessed since its
declaration. These can be replaced with a static initialization
using the STRBUF_INIT macro which is just as readable, saves a
function call, and takes up fewer lines.

Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

exec_cmd.c

@@ -59,9 +59,7 @@ static void add_path(struct strbuf *out, const char *path)
 void setup_path(void)
 {
 	const char *old_path = getenv("PATH");
-	struct strbuf new_path;
-
-	strbuf_init(&new_path, 0);
+	struct strbuf new_path = STRBUF_INIT;
 
 	add_path(&new_path, argv_exec_path);
 	add_path(&new_path, getenv(EXEC_PATH_ENVIRONMENT));