Prepare mbed-tools release 5.4.0

Author: monty-bot

CHANGELOG.md

@@ -12,6 +12,16 @@ beta releases are not included in this history. For a full list of all releases,
 
 [//]: # (begin_release_notes)
 
+5.4.0 (2021-02-03)
+==================
+
+Features
+--------
+
+- Targets removed: EFM32 Tiny Gecko 11, MCB4300.
+  Targets modified: S5JS100. (#20210203050126)
+
+
 5.3.0 (2021-01-30)
 ==================
 

src/mbed_tools/targets/_internal/data/board_database_snapshot.json

@@ -231,16 +231,6 @@
         "mbed_os_support": [],
         "mbed_enabled": []
     },
-    {
-        "board_type": "PLACEHOLDER",
-        "board_name": "MCB4300",
-        "product_code": "0",
-        "target_type": "platform",
-        "slug": "MCB4300",
-        "build_variant": [],
-        "mbed_os_support": [],
-        "mbed_enabled": []
-    },
     {
         "board_type": "MIMXRT1180_EVK",
         "board_name": "MIMXRT1180-EVK",
@@ -738,16 +728,6 @@
             "Baseline"
         ]
     },
-    {
-        "board_type": "EFM32TG11_STK3301",
-        "board_name": "EFM32 Tiny Gecko 11",
-        "product_code": "2043",
-        "target_type": "platform",
-        "slug": "EFM32-Tiny-Gecko-11",
-        "build_variant": [],
-        "mbed_os_support": [],
-        "mbed_enabled": []
-    },
     {
         "board_type": "GD32_E103VB",
         "board_name": "GD32-E103VB",
@@ -980,9 +960,7 @@
         "target_type": "platform",
         "slug": "S5JS100",
         "build_variant": [],
-        "mbed_os_support": [
-            "Mbed OS 5.15"
-        ],
+        "mbed_os_support": [],
         "mbed_enabled": []
     },
     {