help: include fsmonitor--daemon feature flag in version info

Add the "feature: fsmonitor--daemon" message to the output of
`git version --build-options`.

This allows users to know if the built-in fsmonitor feature is
supported on their platform.

Signed-off-by: Jeff Hostetler <jeffhost@microsoft.com>

help.c

@@ -11,6 +11,7 @@
 #include "version.h"
 #include "refs.h"
 #include "parse-options.h"
+#include "fsmonitor-ipc.h"
 
 struct category_description {
 	uint32_t category;
@@ -664,6 +665,9 @@ void get_version_info(struct strbuf *buf, int show_build_options)
 		strbuf_addf(buf, "sizeof-size_t: %d\n", (int)sizeof(size_t));
 		strbuf_addf(buf, "shell-path: %s\n", SHELL_PATH);
 		/* NEEDSWORK: also save and output GIT-BUILD_OPTIONS? */
+
+		if (fsmonitor_ipc__is_supported())
+			strbuf_addstr(buf, "feature: fsmonitor--daemon\n");
 	}
 }