doc: fix format in flow API guide

[ upstream commit 5d254667810fffe59190ca208a078bcb666a2a71 ]

The modify field action description inside "Generic flow API (rte_flow)"
documentation, lists all operations supported for a destination field.
In addition, it lists the values supported for a encapsulation level
field.
Before the lists, in both cases, miss a blank line causing them to look
regular text lines.
This patch adds the blank lines.

The asynchronous operations description inside "Generic flow API
(rte_flow)" documentation, adds some bullets to describe asynchronous
operations behavior.
Before the first bullet, miss a blank line causing it to look a regular
text line.
This patch adds the blank line.

The RSS action description inside "Generic flow API (rte_flow)"
documentation, lists the values supported for a encapsulation level
field.
For "2" value, it uses 3 spaces as an indentation instead of 2 after
line breaking, causing the first line to be bold.
This patch updates the number of spaces in the indentation.

Fixes: 73b68f4 ("ethdev: introduce generic modify flow action")
Fixes: 197e820 ("ethdev: bring in async queue-based flow rules operations")
Fixes: 18aee28 ("ethdev: add encap level to RSS flow API action")

Signed-off-by: Michael Baum <michaelba@nvidia.com>
Acked-by: Ori Kam <orika@nvidia.com>

doc/guides/prog_guide/rte_flow.rst

@@ -2008,8 +2008,8 @@ Also, regarding packet encapsulation ``level``:
   level.
 
 - ``2`` and subsequent values request RSS to be performed on the specified
-   inner packet encapsulation level, from outermost to innermost (lower to
-   higher values).
+  inner packet encapsulation level, from outermost to innermost (lower to
+  higher values).
 
 Values other than ``0`` are not necessarily supported.
 
@@ -3066,20 +3066,23 @@ The immediate value ``RTE_FLOW_FIELD_VALUE`` (or a pointer to it
 ``RTE_FLOW_FIELD_START`` is used to point to the beginning of a packet.
 See ``enum rte_flow_field_id`` for the list of supported fields.
 
-``op`` selects the operation to perform on a destination field.
+``op`` selects the operation to perform on a destination field:
+
 - ``set`` copies the data from ``src`` field to ``dst`` field.
 - ``add`` adds together ``dst`` and ``src`` and stores the result into ``dst``.
-- ``sub`` subtracts ``src`` from ``dst`` and stores the result into ``dst``
+- ``sub`` subtracts ``src`` from ``dst`` and stores the result into ``dst``.
 
 ``width`` defines a number of bits to use from ``src`` field.
 
 ``level`` is used to access any packet field on any encapsulation level
-as well as any tag element in the tag array.
-- ``0`` means the default behaviour. Depending on the packet type, it can
-mean outermost, innermost or anything in between.
+as well as any tag element in the tag array:
+
+- ``0`` means the default behaviour. Depending on the packet type,
+  it can mean outermost, innermost or anything in between.
 - ``1`` requests access to the outermost packet encapsulation level.
 - ``2`` and subsequent values requests access to the specified packet
-encapsulation level, from outermost to innermost (lower to higher values).
+  encapsulation level, from outermost to innermost (lower to higher values).
+
 For the tag array (in case of multiple tags are supported and present)
 ``level`` translates directly into the array index.