[HUST CSE][document] Fix some comments, invalid grouping commands and warnings in Doxygen.

将Doxygen输入文件（由Doxyfile中的INPUT定义）中的失效Doxygen分组指令（如/*@*/和/*@}*/）更改为有效的分组指令（如/**@*/和/**@}*/）；（此处只对INPUT中的文件做了修改，bsp目录下和libcpu目录下存在近万个失效的Doxygen分组指令，但由于不作为文档的输入文件且这些文件过于庞大老旧，没有对这些文件中的无效指令做修改）
将图片文件统一放入了images目录下；
修改了Doxyfile和部分Doxygen注释，使得Doxyfile能够定位到新的代码路径且不受重复实现的影响；
解决了一些注释中的参数名不匹配、参数多余/缺失等问题。

documentation/doxygen/hardware.h

@@ -12,21 +12,21 @@
  * in board, the pinmux setting etc. In RT-Thread RTOS, the bsp is placed under bsp
  * directory.
  *
- * Chip Support Package (CSP) is a software set that contains chip specific software.
+ * Chip Support Package(CSP) is a software set that contains chip specific software.
  * A CSP usually includes operating system porting and peripheral device drivers inside
  * chip. In RT-Thread RTOS, the csp is placed under libcpu directory.
  */
 
 /**
  * @addtogroup bsp
+ * @{
  */
-/*@{*/
 
 /**
  * This function will return current system interrupt status and disable system
  * interrupt.
  *
- * @return the current system interrupt status
+ * @return the current system interrupt status.
  */
 rt_base_t rt_hw_interrupt_disable(void);
 
@@ -34,6 +34,8 @@ rt_base_t rt_hw_interrupt_disable(void);
  * This function will set the specified interrupt status, which shall saved by
  * rt_hw_intterrupt_disable function. If the saved interrupt status is interrupt
  * opened, this function will open system interrupt status.
+ *
+ * @param level the interrupt status to be set.
  */
 void rt_hw_interrupt_enable(rt_base_t level);
 
@@ -70,7 +72,7 @@ void rt_hw_interrupt_umask(int vector);
  * @note not all of platform provide this function.
  */
 void rt_hw_interrupt_install(int vector, rt_isr_handler_t new_handler,
-		rt_isr_handler_t *old_handler);
+                            rt_isr_handler_t *old_handler);
 
 /**
  * This function will reset whole platform.
@@ -82,4 +84,4 @@ void rt_hw_cpu_reset(void);
  */
 void rt_hw_cpu_shutdown(void);
 
-/*@}*/
+/**@}*/