Abseil 2d2a8ae and later does not build against glibc 2.32 and later

**Describe the bug**



Compiling Abseil as a whole, or a target which transitively depends on the `absl::base_internal::StrError`, fails with the following report:



```

FAILED: absl/base/CMakeFiles/strerror.dir/internal/strerror.cc.o 

/usr/bin/c++  -I../ -Wall -Wextra -Wcast-qual -Wconversion-null -Wmissing-declarations -Woverlength-strings -Wpointer-arith -Wunused-local-typedefs -Wunused-result -Wvarargs -Wvla -Wwrite-strings -Wno-missing-field-initializers -Wno-sign-compare -std=gnu++11 -MD -MT absl/base/CMakeFiles/strerror.dir/internal/strerror.cc.o -MF absl/base/CMakeFiles/strerror.dir/internal/strerror.cc.o.d -o absl/base/CMakeFiles/strerror.dir/internal/strerror.cc.o -c ../absl/base/internal/strerror.cc

../absl/base/internal/strerror.cc: In function ‘const char* absl::base_internal::{anonymous}::StrErrorAdaptor(int, char*, size_t)’:

../absl/base/internal/strerror.cc:41:31: error: ‘sys_nerr’ was not declared in this scope

   41 |   if (0 <= errnum && errnum < sys_nerr) {

      |                               ^~~~~~~~

../absl/base/internal/strerror.cc:42:25: error: ‘sys_errlist’ was not declared in this scope

   42 |     if (const char* p = sys_errlist[errnum]) {

      |                         ^~~~~~~~~~~

[13/155] Building CXX object absl/base/CMakeFiles/base.dir/internal/sysinfo.cc.

ninja: build stopped: subcommand failed.

```



**Steps to reproduce the bug**



In the abseil source directory, with a system glibc of 2.32 or later:



```sh

cmake -S . -B build -GNinja -DCMAKE_CXX_STANDARD=11

cmake --build build

```



**What version of Abseil are you using?**

Any including commit `2d2a8aea291c4877e75c7991a61e57d7e12b5373`



**What operating system and version are you using**



Arch Linux (rolling release), with glibc installed at package version 2.32-3



**What compiler and version are you using?**



```

% g++ -v

Using built-in specs.

COLLECT_GCC=g++

COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-pc-linux-gnu/10.2.0/lto-wrapper

Target: x86_64-pc-linux-gnu

Configured with: /build/gcc/src/gcc/configure --prefix=/usr --libdir=/usr/lib --libexecdir=/usr/lib --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=https://bugs.archlinux.org/ --enable-languages=c,c++,ada,fortran,go,lto,objc,obj-c++,d --with-isl --with-linker-hash-style=gnu --with-system-zlib --enable-__cxa_atexit --enable-cet=auto --enable-checking=release --enable-clocale=gnu --enable-default-pie --enable-default-ssp --enable-gnu-indirect-function --enable-gnu-unique-object --enable-install-libiberty --enable-linker-build-id --enable-lto --enable-multilib --enable-plugin --enable-shared --enable-threads=posix --disable-libssp --disable-libstdcxx-pch --disable-libunwind-exceptions --disable-werror gdc_include_dir=/usr/include/dlang/gdc

Thread model: posix

Supported LTO compression algorithms: zlib zstd

gcc version 10.2.0 (GCC) 

```



**What build system are you using?**

cmake version 3.18.2, with ninja version 1.10.1



**Additional context**

T

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