Merge branch 'news_5.4' into 'master'

Update news for 5.4

See merge request !658

NEWS

@@ -12,6 +12,21 @@ Changes for 5.4.0
 - Fixed issue where High-quarter FIFO error would not latch on 18-bit DACs.
 - DAQ wiper no supports test stands by default.
 ==================================================================================================
+Changes for 5.4.0
+==================================================================================================
+- Initial functionality for new stateSpace part has been added.
+  https://git.ligo.org/cds/software/advligorts/-/wikis/State-space-Part
+- Fixing regression bug where externally clocked test systems would no longer work after RCG 5.1+
+  if they had more than one ADC.
+- A model's build will now fail if more than 64 RFM IPCs have been allocated, instead of silently
+  failing.
+- IOP model name's don't have to start with <IFO>iop... and can now be named IFOxyz...
+- Added IPC statistics for the new wait logic, avg/max wait time, slow IPC index, etc.
+- Added the ability for models to wait for late IPC data if they have processing headroom.
+- VIO models clean up their mbufs.
+- 18 bit DACs now correctly report FIFO HIQTR errors.
+- Dolphin timing xmiters now show that they are driving time on their GDS_TP screens.
+==================================================================================================
 Changes for 5.3.0
 ==================================================================================================
 - Adding support for the new LIGO 28AO32 DAC modules.