Update gdb on AT 12.0
Update gdb on AT 12.0

Bump to version 8.2.1
Bump to revision dc359e9889b5

Signed-off-by: Erwan Prioul <9949cc68615082c237e6af925cacbd2ea7f2e953@linux.ibm.com>

advancetoolchain/advance-toolchain,advancetoolchain/advance-toolchain,advancetoolchain/advance-toolchain,advancetoolchain/advance-toolchain,advancetoolchain/advance-toolchain,advancetoolchain/advance-toolchain