Add Cortex-M architecture HAL, STM32 variant and STM3210E platform HALs. Add STM32 serial driver and on-chip flash driver. Fix some compile problems with dlmalloc. See the various ChangeLogs for details.

/* this is a simple hello world program */
#include <stdio.h>

int main(void)
{
  printf("Hello, eCos world!\n");
  return 0;
}