bifrost: Fix packing of ADD_FEXP2_FAST

This was being packed as 1-src and so the Src1 was not set up properly.
It only worked by accident.

Signed-off-by: Chris Forbes <chrisforbes@google.com>
Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6111>
diff --git a/src/panfrost/bifrost/bi_pack.c b/src/panfrost/bifrost/bi_pack.c
index 5fb8213..d4351e2 100644
--- a/src/panfrost/bifrost/bi_pack.c
+++ b/src/panfrost/bifrost/bi_pack.c
@@ -1433,7 +1433,7 @@
 
         } else if (ins->op.special == BI_SPECIAL_EXP2_LOW) {
                 assert(!fp16);
-                op = BIFROST_ADD_OP_FEXP2_FAST;
+                return bi_pack_add_2src(ins, regs, BIFROST_ADD_OP_FEXP2_FAST);
         } else if (ins->op.special == BI_SPECIAL_IABS) {
                 assert(ins->src_types[0] == nir_type_int32);
                 op = BIFROST_ADD_OP_IABS_32;
diff --git a/src/panfrost/bifrost/bifrost.h b/src/panfrost/bifrost/bifrost.h
index 085b329..12fb13a 100644
--- a/src/panfrost/bifrost/bifrost.h
+++ b/src/panfrost/bifrost/bifrost.h
@@ -163,7 +163,6 @@
 #define BIFROST_ADD_OP_FRSQ_FAST_F16_X (0x0ce50)
 #define BIFROST_ADD_OP_FRSQ_FAST_F16_Y (0x0ce70)
 #define BIFROST_ADD_OP_LOG2_HELP  (0x0cc68)
-#define BIFROST_ADD_OP_FEXP2_FAST (0x0cd58)
 #define BIFROST_ADD_OP_IABS_32 (0x07bd4)
 
 struct bifrost_add_inst {
@@ -203,6 +202,7 @@
 #define BIFROST_ADD_ISUB_8  (0x17a80 >> 3)
 #define BIFROST_ADD_ISUB_16 (0x17b00 >> 3)
 #define BIFROST_ADD_ISUB_32 (0x17ac0 >> 3)
+#define BIFROST_ADD_OP_FEXP2_FAST (0x0cd58 >> 3)
 
 struct bifrost_add_2src {
         unsigned src0 : 3;