docs: update buildah-from, buildah-pull 'platform' option compatibili…

…ty notes

Signed-off-by: James Addison <jay@jp-hosting.net>

docs/buildah-from.1.md

@@ -299,9 +299,7 @@ process.
 
 Set the OS/ARCH of the image to be pulled
 to the provided value instead of using the current operating system and
-architecture of the host (for example `linux/arm`). If `--platform`
-is set, then the values of the `--arch`, `--os`, and `--variant` options will
-be overridden.
+architecture of the host (for example `linux/arm`).
 
 OS/ARCH pairs are those used by the Go Programming Language.  In several cases
 the ARCH value for a platform differs from one produced by other tools such as
@@ -313,6 +311,8 @@ While `buildah from` is happy to pull an image for any platform that exists,
 `buildah run` will not be able to run binaries provided by that image without
 the help of emulation provided by packages like `qemu-user-static`.
 
+**NOTE:** The `--platform` option may not be used in combination with the `--arch`, `--os`, or `--variant` options.
+
 **--pull**
 
 When the flag is enabled, attempt to pull the latest image from the registries

docs/buildah-pull.1.md

@@ -64,16 +64,16 @@ Set the OS of the image to be pulled instead of using the current operating syst
 
 Set the OS/ARCH of the image to be pulled
 to the provided value instead of using the current operating system and
-architecture of the host (for example `linux/arm`).  If `--platform`
-is set, then the values of the `--arch`, `--os`, and `--variant` options will
-be overridden.
+architecture of the host (for example `linux/arm`).
 
 OS/ARCH pairs are those used by the Go Programming Language.  In several cases
 the ARCH value for a platform differs from one produced by other tools such as
 the `arch` command.  Valid OS and architecture name combinations are listed as
 values for $GOOS and $GOARCH at https://golang.org/doc/install/source#environment,
 and can also be found by running `go tool dist list`.
 
+**NOTE:** The `--platform` option may not be used in combination with the `--arch`, `--os`, or `--variant` options.
+
 **--policy**=**always**|**missing**|**never**
 
 Pull image policy. The default is **missing**.