Build failure on x32 (gdb 11.1)

[Jan Palus]

gdb 11.1 fails during compilation on x32 ABI:

../.././gdbserver/../gdb/nat/amd64-linux-siginfo.c:280:42: error: 'struct compat_x32_siginfo_t::<unnamed union>::<unnamed>' has no member named 'si_addr_bnd'
280 | #define cpt_si_lower _sifields._sigfault.si_addr_bnd._lower
| ^~~~~~~~~~~
../.././gdbserver/../gdb/nat/amd64-linux-siginfo.c:337:38: note: in expansion of macro 'cpt_si_lower'
337 | to->cpt_si_lower = from_ptrace.cpt_si_lower;
| ^~~~~~~~~~~~
../.././gdbserver/../gdb/nat/amd64-linux-siginfo.c:281:42: error: 'struct compat_x32_siginfo_t::<unnamed union>::<unnamed>' has no member named 'si_addr_bnd'
281 | #define cpt_si_upper _sifields._sigfault.si_addr_bnd._upper
| ^~~~~~~~~~~
../.././gdbserver/../gdb/nat/amd64-linux-siginfo.c:338:38: note: in expansion of macro 'cpt_si_upper'
338 | to->cpt_si_upper = from_ptrace.cpt_si_upper;
| ^~~~~~~~~~~~

I believe it is caused by https://sourceware.org/git/?p=binutils-gdb.git;a=commitdiff;h=d3d7d1b