patch 8.2.1904: still using default option values after using ":badd +1"

Problem:    Still using default option values after using ":badd +1".
Solution:   Find a window where options were set.  Don't set the window when
            using ":badd".
diff --git a/src/vim.h b/src/vim.h
index 64cf6d4..4e40c81 100644
--- a/src/vim.h
+++ b/src/vim.h
@@ -931,6 +931,7 @@
 #define BLN_NOOPT	16	// don't copy options to existing buffer
 #define BLN_DUMMY_OK	32	// also find an existing dummy buffer
 #define BLN_REUSE	64	// may re-use number from buf_reuse
+#define BLN_NOCURWIN	128	// buffer is not associated with curwin
 
 // Values for in_cinkeys()
 #define KEY_OPEN_FORW	0x101