Zero-sized symbol on end of section

[shenhanc78]

Hi, we got an internal error for a symbol sitting right on the edge of section end.

  [13] xxx_malloc        PROGBITS        00000000238aa800 238aa800 001c7a 00  AX  0   0 64
  [14] malloc_hook       PROGBITS        00000000238ac480 238ac480 0006c2 00  AX  0   0 16

And we have a symbol with size 0 sitting exactly on the end of the section.
xxx at 0x238ac47a = (00000000238aa800 + 001c7a)
So BinaryContext::getSectionFromAddress fails to find a home for the symbol.

The fix is straightforward, does it make sense to you to include zero-sized symbol on edge of section end?