Standalone bsp os fails to build under mb-g++

When the os compiler option is set to "mb-g++", Standalone OS will fail to build with following errors:

xil_mem.c: In function 'void Xil_MemCpy(void*, const void*, u32)':
xil_mem.c:50:25: error: invalid conversion from 'const void*' to 'const char*' [-fpermissive]
50 | const char s = src;
| ^~~
| |
| const void

xil_sutil.c:880:24: error: invalid conversion from 'void*' to 'u8*' {aka 'unsigned char*'} [-fpermissive]
880 | u8 DestTemp = Dest;
| ^~~~
| |
| void
xil_sutil.c:881:29: error: invalid conversion from 'const void*' to 'const u8*' {aka 'const unsigned char*'} [-fpermissive]
881 | const u8 SrcTemp = Src;
| ^~~
| |
| const void

xil_util.c:554:26: error: invalid conversion from 'const void*' to 'const u8*' {aka 'const unsigned char*'} [-fpermissive]
554 | const u8 Buf1 = Buf1Ptr;
| ^~~~~~~
| |
| const void
xil_util.c:555:26: error: invalid conversion from 'const void*' to 'const u8*' {aka 'const unsigned char*'} [-fpermissive]
555 | const u8 Buf2 = Buf2Ptr;
| ^~~~~~~
| |
| const void

This was tested with v9.2 of the Standalone OS. It is highly expected that older versions are also affected by this.

All the flagged bugs above require explicit casting from void* to target type.

Start with xil_mem.c:50, xil_sutil.c:880-881, and xil_util.c:554-555, then reproduce the Standalone OS build with the os compiler option set to mb-g++. Check that the affected pointer assignments are accepted under this compiler and that the build completes without the reported conversion errors.