Update GMP-ECM to 6.2.2

[mabshoff]

Changes between ecm-6.2.1 and ecm-6.2.2:
* Updated build project files for Visual C by Brian Gladman, also adds
missing NTT_GFP_TWIDDLE_DI[FT]_BREAKOVER defines in VC parameter file
* Fixed uninitialised parameter to P-1 probability computation
* In tune.c : fixed generation of NTT_GFP_TWIDDLE_DI[FT]_BREAKOVER values,
avoid calling cputime() excessively often when timing short functions,
fixed access to uninitialised memory
* Fixed serious split infinitive in configure script (thanks Paul Leyland)
* Removed unnecessary carry propagation in x86_64 mulredc code, slight
speedup (thanks Philip McLaughlin)
* Fixed non-portable PIC code in x86_64/redc.asm
* Fixed problem with pattern matching host type names in configure.in
* Converted binary constants in spv.c and ntt_gfp.c to hexadecimal,
some assembler do not support binary constants

Cheers,

Michael