Update rsync command.

Update the rsync command to avoid duplication of newlib libraries.

See GNUTOOLS-13897

Change-Id: Ie1ba6a82b41516528b41bb8bd92d71dff7740e33
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/c/dsg-gnu/Internal/gnu-devtools-for-arm/+/751430


Tested-by: Service account - used by users in DSG GNU team <dgboter@arm.com>
Reviewed-by: Vaseeharan Vinayagamoorthy <vaseeharan.vinayagamoorthy@arm.com>
Tested-by: Daniel Fellows <daniel.fellows@arm.com>
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/c/dsg-gnu/Internal/gnu-devtools-for-arm/+/751498


Reviewed-by: Daniel Fellows <daniel.fellows@arm.com>