In GenerateTooltipContent(): Fixed logic for displaying TRAINER acquire-type.

diff --git a/Frame.lua b/Frame.lua
index 75ad32e..8627a0b 100644
--- a/Frame.lua
+++ b/Frame.lua
@@ -711,7 +711,7 @@ do
 				for id_num in pairs(acquire_info) do
 					local trainer = private.trainer_list[id_num]

-					if location_id and trainer.location == location_id then
+					if not location_id or trainer.location == location_id then
 						local display_tip = false

 						color_1 = CATEGORY_COLORS["trainer"]