[llvm-objdump] Fix spurious "The end of the file was unexpectedly encountered" if a SHT_NOBITS sh_offset is larger than the file size
llvm-objdump -D this file:
int a[100000];
int main() { return 0; }
Will produce an error: "The end of the file was unexpectedly encountered".
This happens because of a check in Binary.h checkOffset. (Addr + Size > M.getBufferEnd()).
The sh_offset and sh_size fields can be ignored for SHT_NOBITS sections.
Fix the error by changing ELFObjectFile<ELFT>::getSectionContents to use
the file base for SHT_NOBITS sections.
Reviewed By: grimar, MaskRay
Differential Revision: https://reviews.llvm.org/D69192