[lldb] Remove obsolete Android-specific definitions

[pirama]

Summary

Bionic's <sys/procfs.h> defines the necessary symbols. Remove the
specialization for Android and the now-unnecessary include of
<sys/ptrace.h>. This also helps resolve issues when building the
x86/x86_64 lldb-server for Android.

Curiously, the default branch to include <sys/procfs.h> doesn't seem
necessary on Linux. I'll remove it and add it back if it breaks other
builders.

[srhines]

Thanks for cleaning this up!

lldb/source/Plugins/Process/Linux/Procfs.h

 //===-- Procfs.h ---------------------------------------------- -*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
-// source/Plugins/Process/Linux/Procfs.h defines the symbols we need from
-// sys/procfs.h on Android/Linux for all supported architectures.
-
 #include "lldb/lldb-types.h"
 #include "llvm/Support/Error.h"
-#include <sys/ptrace.h>
 #include <vector>
 
-#ifdef __ANDROID__
-#if defined(__arm64__) || defined(__aarch64__)
-typedef unsigned long elf_greg_t;
-typedef elf_greg_t
-    elf_gregset_t[(sizeof(struct user_pt_regs) / sizeof(elf_greg_t))];
-typedef struct user_fpsimd_state elf_fpregset_t;
-#ifndef NT_FPREGSET
-#define NT_FPREGSET NT_PRFPREG
-#endif // NT_FPREGSET
-#elif defined(__mips__)
-#ifndef NT_FPREGSET
-#define NT_FPREGSET NT_PRFPREG
-#endif // NT_FPREGSET
-#endif
-#else // __ANDROID__
-#include <sys/procfs.h>
-#endif // __ANDROID__
-
 namespace lldb_private {
 namespace process_linux {
 
 /// \return
 ///     The content of /proc/cpuinfo and cache it if errors didn't happen.
 llvm::Expected<llvm::ArrayRef<uint8_t>> GetProcfsCpuInfo();
 
 /// \return