[mlir][linalg] NFC: Rename SVE integration tests directory from Scalable to ArmSVE

ArmSME is also 'Scalable' but since these tests are predicated on
different configuration flags they can't live in the same directory, so
it makes sense to rename this directory to ArmSVE. This is also
consistent with Vector CPU integration tests.

Reviewed By: awarzynski

Differential Revision: https://reviews.llvm.org/D158712