Update last year's droidcon Bangladesh entry with CfP info

Author: balazsgerlei

_conferences/droidcon-bangladesh-2025.md

@@ -1,8 +1,13 @@
 ---
 name: "Droidcon"
 website: https://bd.droidcon.com/
-location: Bangladesh
+location: Dhaka, Bangladesh
 
 date_start: 2025-06-20
 date_end:   2025-06-21
+
+cfp:
+  start: 2025-01-25
+  end:   2025-04-17
+  site: https://sessionize.com/bd_droidcon_cfp/
 ---