igb: Clear IMS bits when committing ICR access

The datasheet says contradicting statements regarding ICR accesses so it
is not reliable to determine the behavior of ICR accesses. However,
e1000e does clear IMS bits when reading ICR accesses and Linux also
expects ICR accesses will clear IMS bits according to:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/net/ethernet/intel/igb/igb_main.c?h=v6.2#n8048

Fixes: 3a977de ("Intrdocue igb device emulation")
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Sriram Yagnaraman <sriram.yagnaraman@est.tech>
Signed-off-by: Jason Wang <jasowang@redhat.com>

hw/net/igb_core.c

@@ -2452,16 +2452,16 @@ igb_set_ims(IGBCore *core, int index, uint32_t val)
 static void igb_commit_icr(IGBCore *core)
 {
     /*
-     * If GPIE.NSICR = 0, then the copy of IAM to IMS will occur only if at
+     * If GPIE.NSICR = 0, then the clear of IMS will occur only if at
      * least one bit is set in the IMS and there is a true interrupt as
      * reflected in ICR.INTA.
      */
     if ((core->mac[GPIE] & E1000_GPIE_NSICR) ||
         (core->mac[IMS] && (core->mac[ICR] & E1000_ICR_INT_ASSERTED))) {
-        igb_set_ims(core, IMS, core->mac[IAM]);
-    } else {
-        igb_update_interrupt_state(core);
+        igb_clear_ims_bits(core, core->mac[IAM]);
     }
+
+    igb_update_interrupt_state(core);
 }
 
 static void igb_set_icr(IGBCore *core, int index, uint32_t val)