soc: ti: k3-navss-ringacc: Fix reconfiguration of qmode API

Function "k3_ringacc_ring_reconfig_qmode_raw()" should reset qmode to
requested value and should not update other fields in ring configuration
register.

Signed-off-by: Chintan Vankar <c-vankar@ti.com>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
Reviewed-by: Vignesh Raghavendra <vigneshr@ti.com>