[beken-72xx] Fix Arduino delay(), fix reading heap size

arduino/beken-72xx/cores/arduino/LibreTuyaAPI.cpp

@@ -79,7 +79,16 @@ uint32_t LibreTuya::getRamSize() {
 }
 
 uint32_t LibreTuya::getHeapSize() {
+#if configDYNAMIC_HEAP_SIZE
+	extern unsigned char _empty_ram;
+#if CFG_SOC_NAME == SOC_BK7231N
+	return (0x00400000 + 192 * 1024) - (uint32_t)(&_empty_ram);
+#else
+	return (0x00400000 + 256 * 1024) - (uint32_t)(&_empty_ram);
+#endif
+#else
 	return configTOTAL_HEAP_SIZE;
+#endif
 }
 
 uint32_t LibreTuya::getFreeHeap() {

arduino/beken-72xx/cores/arduino/WVariant.h

@@ -9,6 +9,10 @@ extern "C" {
 #include "sdk_extern.h"
 #include "sdk_mem.h"
 
+// allow BDK use its own delay() and let Arduino code use delayMilliseconds()
+void delayMilliseconds(unsigned long);
+#define delay delayMilliseconds
+
 #ifdef __cplusplus
 } // extern "C"
 #endif

arduino/beken-72xx/cores/arduino/wiring.c

@@ -4,10 +4,9 @@
 #include <rtos_pub.h>
 #include <sys_rtos.h>
 
-// TODO work out this conflicting with func/misc/target_util.c
-/* void delay(unsigned long ms) {
+void delayMilliseconds(unsigned long ms) {
 	rtos_delay_milliseconds(ms);
-} */
+}
 
 void delayMicroseconds(unsigned int us) {}