scsi: docs: convert link_power_management_policy.txt to ReST

Link: https://lore.kernel.org/r/c56177fdf046d80e0dec6031c4139cb4e8c39d31.1583136624.git.mchehab+huawei@kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Documentation/scsi/index.rst

@@ -24,5 +24,6 @@ Linux SCSI Subsystem
    hpsa
    hptiop
    libsas
+   link_power_management_policy
 
    scsi_transport_srp/figures

Documentation/scsi/link_power_management_policy.rst

@@ -1,8 +1,15 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+==========================
+Link Power Managent Policy
+==========================
+
 This parameter allows the user to set the link (interface) power management.
 There are 3 possible options:
 
+=====================   =====================================================
 Value			Effect
-----------------------------------------------------------------------------
+=====================   =====================================================
 min_power		Tell the controller to try to make the link use the
 			least possible power when possible.  This may
 			sacrifice some performance due to increased latency
@@ -15,5 +22,4 @@ max_performance		Generally, this means no power management.  Tell
 medium_power		Tell the controller to enter a lower power state
 			when possible, but do not enter the lowest power
 			state, thus improving latency over min_power setting.
-
-
+=====================   =====================================================