patch 9.0.0977: it is not easy to see what client-server commands are doing

Problem:    It is not easy to see what client-server commands are doing.
Solution:   Add channel log messages if ch_log() is available.  Move the
            channel logging and make it available with the +eval feature.
diff --git a/src/os_win32.c b/src/os_win32.c
index acbc4cb..334d973 100644
--- a/src/os_win32.c
+++ b/src/os_win32.c
@@ -2222,7 +2222,7 @@
 	buf[len++] = typeahead[0];
 	mch_memmove(typeahead, typeahead + 1, --typeaheadlen);
     }
-# ifdef FEAT_JOB_CHANNEL
+# ifdef FEAT_EVAL
     if (len > 0)
     {
 	buf[len] = NUL;
@@ -4923,7 +4923,7 @@
     int		tmode = cur_tmode;
     WCHAR	szShellTitle[512];
 
-#ifdef FEAT_JOB_CHANNEL
+#ifdef FEAT_EVAL
     ch_log(NULL, "executing shell command: %s", cmd);
 #endif
     // Change the title to reflect that we are in a subshell.