[llvm-readelf] - Print unknown st_other value if present in GNU output.

[llvm-readelf] - Print unknown st_other value if present in GNU output.

This is a fix for https://bugs.llvm.org/show_bug.cgi?id=40785.

llvm-readelf does not print the st_value of the symbol when
st_value has any non-visibility bits set.

This patch:

* Aligns "Ndx" row for the default and a new cases.
(it was 1 space character off for the case when "PROTECTED" visibility was printed)

* Prints "[<other>: 0x??]" for symbols which has an additional st_other bits set.
In compare with GNU, this logic is a bit simpler and seems to be more consistent.

For MIPS GNU can print named flags, though can't print a mix of them:
0: 00000000 0 NOTYPE LOCAL DEFAULT UND
1: 00000000 0 NOTYPE GLOBAL DEFAULT [OPTIONAL] UND a1
2: 00000000 0 NOTYPE GLOBAL DEFAULT [MIPS PLT] UND a2
3: 00000000 0 NOTYPE GLOBAL DEFAULT [MIPS PIC] UND a3
4: 00000000 0 NOTYPE GLOBAL DEFAULT [MICROMIPS] UND a4
5: 00000000 0 NOTYPE GLOBAL DEFAULT [MIPS16] UND a5
6: 00000000 0 NOTYPE GLOBAL DEFAULT [<other>: c] UND b1
7: 00000000 0 NOTYPE GLOBAL DEFAULT [<other>: 28] UND b2

On PPC64 it can print a localentry value that is encoded in the high bits of st_other
63: 0000000000000850 208 FUNC GLOBAL DEFAULT [<localentry>: 8] 12

We chose to print the raw st_other field, prefixed with '0x'.

Differential revision: https://reviews.llvm.org/D67094

llvm-svn: 371201