Revision 3 updates gdb to version 11.2.0.
This is not necessarily needed for building, but I think it's better to
have the same toolchain as the Qt SDK.
Task-number: QTBUG-101653
Pick-to: 6.3 6.2
Change-Id: I92a319a943d18ec10e5e0da3cd770ba7cde26f13
Reviewed-by: Tony Sarajärvi <tony.sarajarvi@qt.io>