[spinel] add support for logging crash dumps (#10061)

This commit adds a new feature that allows platforms to log crash logs.

### Additions
- `void otPlatLogCrashDump(void)` - API that logs a crash dump using
  OpenThread Logging APIs
- `SPINEL_PROP_RCP_LOG_CRASH_DUMP` - spinel prop that calls
  `otPlatLogCrashDump()` when `Set`
- `SPINEL_CAP_RCP_LOG_CRASH_DUMP` - spinel capability denoting that a
  RCP supports logging crash dumps

### Usage
- For `ot-cli-ftd|mtd`, `otPlatLogCrashDump()` is called at the end of
  app initialization, before the main loop. See [main.c]
- For Host/RCP setups, during initialization, the Host gets the RCP
  capabilities. If the RCP has the `SPINEL_CAP_RCP_LOG_CRASH_DUMP`
  capability, the Host will `Set` the `SPINEL_PROP_RCP_LOG_CRASH_DUMP`
  property, triggering the RCP to call `otPlatLogCrashDump()`.
  - If RCP Recovery is enabled, the this will also happen once the RCP
    has been restored

script/test

@@ -104,6 +104,7 @@ build_simulation()
         "-DOT_MESSAGE_USE_HEAP=OFF"
         "-DOT_NETDATA_PUBLISHER=ON"
         "-DOT_PING_SENDER=ON"
+        "-DOT_PLATFORM_LOG_CRASH_DUMP=ON"
         "-DOT_REFERENCE_DEVICE=ON"
         "-DOT_SERVICE=ON"
         "-DOT_SRP_CLIENT=ON"
@@ -173,6 +174,7 @@ build_posix()
         "-DBUILD_TESTING=ON"
         "-DOT_MESSAGE_USE_HEAP=ON"
         "-DOT_PLATFORM_BOOTLOADER_MODE=ON"
+        "-DOT_PLATFORM_LOG_CRASH_DUMP=ON"
         "-DOT_THREAD_VERSION=${version}"
     )