Initial release

This is rebased onto crash-7.2.5 (commit c0a2fc9d322cf0c5f569ce54e9201d2f586edb0c).

Changelog:

New features:

• MIPS: Add MIPS64 support
• MIPS: Add gcore extension (the original crash-gcore-command-1.5.0)
• MIPS: extensions: Add gcore MIPS64 support
• MIPS64: Use precompilation macro to force KVSTART to be defined (correctly)
• MIPS64: Add support for 3-level page tables
• MIPS: Use precompilation macro to force PHYS_START to be defined (correctly)

Bugs:

• MIPS: Fix missing _stext symbol value
• MIPS: Add PHYS_START for PTOV and VTOP
• MIPS: Check MIPS64 before MIPS in set_initial_target()
• task: Fix "panic task not found"
• MIPS: extensions: gcore: Do not hard code page size for mips32
• MIPS: Exclude pages without READ|WRITE (even PRESENT)
• MIPS: Fix kernel address translation
• task/signal: pid: fix for Linux 4.19-rc1 and later kernels
• MIPS64: VTOP: Separate 32b compatibility address space and xkphys
• MIPS64: Limit vmalloc address under 0xffffffff80000000
• MIPS: Fix compiler warnings about data type in fprintf format
• MIPS: Exclude pages below PHYS_START
• Standalone gdb-7.6: MIPS64: Fix wrong program offset into bfd elfcore note description data
• KVADDR: Add sanity checks