scsi: ufs-qcom: Remove testbus dump in ufs_qcom_dump_dbg_regs

Dumping testbus registers outputs a lot of information and can cause
stability issues. Remove the dump code.

Link: https://lore.kernel.org/r/1596975355-39813-4-git-send-email-cang@codeaurora.org
Reviewed-by: Hongwu Su <hongwus@codeaurora.org>
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>