libsparse: Add .clang-format and reformat to google3 style

Bug: 78793464
Test: compiles
Change-Id: I8e44ba77195a12fc2bac7d4276bbc4aa95149b31
diff --git a/libsparse/defs.h b/libsparse/defs.h
index 34e63c5..28e5cab 100644
--- a/libsparse/defs.h
+++ b/libsparse/defs.h
@@ -17,7 +17,7 @@
 #ifndef _LIBSPARSE_DEFS_H_
 
 #ifndef __unused
-#define __unused        __attribute__((__unused__))
+#define __unused __attribute__((__unused__))
 #endif
 
 #endif /* _LIBSPARSE_DEFS_H_ */