patch 8.2.3208: dynamic library load error does not mention why it failed

Problem:    Dynamic library load error does not mention why it failed.
Solution:   Add the error message. (Martin Tournoij, closes #8621)
diff --git a/src/globals.h b/src/globals.h
index 4737adc..1a24512 100644
--- a/src/globals.h
+++ b/src/globals.h
@@ -1632,7 +1632,7 @@
 	|| defined(DYNAMIC_MZSCHEME) \
 	|| defined(DYNAMIC_LUA) \
 	|| defined(FEAT_TERMINAL)
-EXTERN char e_loadlib[]	INIT(= N_("E370: Could not load library %s"));
+EXTERN char e_loadlib[]	INIT(= N_("E370: Could not load library %s: %s"));
 EXTERN char e_loadfunc[]	INIT(= N_("E448: Could not load library function %s"));
 #endif
 EXTERN char e_nobang[]	INIT(= N_("E477: No ! allowed"));