Update GH man pages

Signed-off-by: OFIWG Bot <[email protected]>

main/man/fi_pingpong.1.md

@@ -72,7 +72,7 @@ given domains cannot communicate, then the application will fail.
 ## Fabric Filtering
 
 *-p \<provider_name\>*
-: The name of the underlying fabric provider (e.g., sockets, psm3, etc.).
+: The name of the underlying fabric provider (e.g., sockets, psm3, usnic, etc.).
   If a provider is not specified via the -p switch, the test will pick one from
   the list of available providers (as returned by fi_getinfo(3)).
 
@@ -119,26 +119,26 @@ given domains cannot communicate, then the application will fail.
 ## An example with various options
 
 ### Server:
-`server$ fi_pingpong -p tcp -I 1000 -S 1024`
+`server$ fi_pingpong -p usnic -I 1000 -S 1024`
 
 ### Client:
-`client$ fi_pingpong -p tcp -I 1000 -S 1024 192.168.0.123`
+`client$ fi_pingpong -p usnic -I 1000 -S 1024 192.168.0.123`
 
 
 Specifically, this will run a pingpong test with:
 
-- tcp provider
+- usNIC provider
 - 1000 iterations
 - 1024 bytes message size
 - server node as 192.168.0.123
 
 ## A longer test
 
 ### Server:
-`server$ fi_pingpong -p tcp -I 10000 -S all`
+`server$ fi_pingpong -p usnic -I 10000 -S all`
 
 ### Client:
-`client$ fi_pingpong -p tcp -I 10000 -S all 192.168.0.123`
+`client$ fi_pingpong -p usnic -I 10000 -S all 192.168.0.123`
 
 
 # DEFAULTS

main/man/fi_provider.7.md

@@ -67,6 +67,10 @@ The following core providers are built into libfabric by default, assuming
 all build pre-requisites are met.  That is, necessary libraries are installed,
 operating system support is available, etc.  This list is not exhaustive.
 
+*CXI*
+: Provider for Cray's Slingshot network. See
+  [`fi_cxi`(7)](fi_cxi.7.html) for more information.
+
 *EFA*
 : A provider for the [Amazon EC2 Elastic Fabric Adapter
   (EFA)](https://aws.amazon.com/hpc/efa/), a custom-built OS bypass