dirstate: make dirstate flags char be unsigned Since https://phab.mercurial-scm.org/D11387, `CC='clang -Werror' make local` has started failing like this: ``` mercurial/cext/util.h:41:50: error: implicit conversion from 'int' to 'char' changes value from 128 to -128 [-Werror,-Wconstant-conversion] static const char dirstate_flag_rust_special = 1 << 7; ~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~^~~~ ``` This patch fixes that by making the flags be an unsigned char. That also matches the `bool` typedef we have in `util.h`, which seems good since many of the `dirstate_item_c_*()` functions return a `bool`. Differential Revision: https://phab.mercurial-scm.org/D11444

--- a/mercurial/cext/parsers.c	Thu Sep 02 03:59:35 2021 +0200
+++ b/mercurial/cext/parsers.c	Thu Sep 16 16:29:55 2021 -0700
@@ -144,9 +144,10 @@
 
 static inline bool dirstate_item_c_added(dirstateItemObject *self)
 {
-	char mask = (dirstate_flag_wc_tracked | dirstate_flag_p1_tracked |
-	             dirstate_flag_p2_tracked);
-	char target = dirstate_flag_wc_tracked;
+	unsigned char mask =
+	    (dirstate_flag_wc_tracked | dirstate_flag_p1_tracked |
+	     dirstate_flag_p2_tracked);
+	unsigned char target = dirstate_flag_wc_tracked;
 	return (self->flags & mask) == target;
 }