pan/bi: Rename I->action to I->flow

For consistency with the Valhall ISA.

Signed-off-by: Alyssa Rosenzweig <alyssa@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15223>

src/panfrost/bifrost/compiler.h

@@ -390,8 +390,8 @@ typedef struct {
         enum bi_register_format register_format;
         enum bi_vecsize vecsize;
 
-        /* Action (flow control) associated with a Valhall instruction */
-        uint8_t action;
+        /* Flow control associated with a Valhall instruction */
+        uint8_t flow;
 
         /* Can we spill the value written here? Used to prevent
          * useless double fills */