[posix] move core config options from cmake file to the header file (#4713)

This commit moves the OpenThread core config definitions (like
`OPENTHREAD_CONFIG_LOG_OUTPUT`) from the `CMakeLists.txt` file into
the `openthread-core-posix-config.h`. This help allow a project/user
specific config header file to override the default config definition
(e.g., toranj config for posix).

src/posix/platform/CMakeLists.txt

@@ -44,9 +44,6 @@ if(NOT OT_CONFIG)
 endif()
 
 list(APPEND OT_PLATFORM_DEFINES
-    "OPENTHREAD_CONFIG_LOG_LEVEL_DYNAMIC_ENABLE=1"
-    "OPENTHREAD_CONFIG_LOG_OUTPUT=OPENTHREAD_CONFIG_LOG_OUTPUT_PLATFORM_DEFINED"
-    "OPENTHREAD_CONFIG_NCP_UART_ENABLE=1"
     "OPENTHREAD_POSIX=1"
     "OPENTHREAD_POSIX_CONFIG_RCP_UART_ENABLE=1"
 )

src/posix/platform/openthread-core-posix-config.h

@@ -44,6 +44,30 @@
 #define OPENTHREAD_CONFIG_LOG_PLATFORM 1
 #endif
 
+/**
+ * @def OPENTHREAD_CONFIG_LOG_OUTPUT
+ *
+ * Select the log output.
+ *
+ */
+#ifndef OPENTHREAD_CONFIG_LOG_OUTPUT
+#define OPENTHREAD_CONFIG_LOG_OUTPUT OPENTHREAD_CONFIG_LOG_OUTPUT_PLATFORM_DEFINED
+#endif
+
+/**
+ * @def OPENTHREAD_CONFIG_LOG_LEVEL_DYNAMIC_ENABLE
+ *
+ * Define as 1 to enable dynamic log level control.
+ *
+ * Note that the OPENTHREAD_CONFIG_LOG_LEVEL determines the log level at
+ * compile time. The dynamic log level control (if enabled) only allows
+ * decreasing the log level from the compile time value.
+ *
+ */
+#ifndef OPENTHREAD_CONFIG_LOG_LEVEL_DYNAMIC_ENABLE
+#define OPENTHREAD_CONFIG_LOG_LEVEL_DYNAMIC_ENABLE 1
+#endif
+
 /**
  * @def OPENTHREAD_CONFIG_PLATFORM_INFO
  *