Fixes and improvements for source builds

[maleadt]

• A GMP patch was malformed; copy the corrected version from Yggdrasil
• Always invoke patch with -f to avoid interactive prompts during build
• Don't quote the path to python, or nghttp2's configure script fails with error: Python interpreter is too old (but config.log reveals "/usr/bin/python": No such file or directory)

[maleadt]

What remains when building with USE_BINARYBUILDER:=0, is that every time you do make there's' a warning about the uninstallers:

❯ make
WARNING: using mismatched version for csl:
  want
  To resolve this warning, you could try either of the following suggestions:
  1. Run the following command: make -C deps uninstall
  2. Remove the following directory: /home/tim/Julia/src/julia/usr
WARNING: using mismatched version for lld:
  want
  To resolve this warning, you could try either of the following suggestions:
  1. Run the following command: make -C deps uninstall
  2. Remove the following directory: /home/tim/Julia/src/julia/usr
removed './bin/7z'

Not pretty, but not fatal either. Maybe @vtjnash has a suggestion on how to avoid this.

[nickrobinson251]

thanks for fixing this! Can we back-port this to the backports-release-1.10 branch please?

[vchuravy]

This broke things on cygwin:

$ make print-PYTHONmake: /cygdrive/c/Program: No such file or directory
/bin/sh: /cygdrive/c/Program: No such file or directory/home/Administrator/julia/Make.inc:1220: normalize_triplet.py appears to be non-functional 
(used python interpreter "/cygdrive/c/Program Files/Python38/python"), so BinaryBuilder disabled
/bin/sh: /cygdrive/c/Program: No such file or directory
/bin/sh: /cygdrive/c/Program: No such file or directory
/bin/sh: /cygdrive/c/Program: No such file or directory
/bin/sh: /cygdrive/c/Program: No such file or directory
/bin/sh: /cygdrive/c/Program: No such file or directory
/bin/sh: /cygdrive/c/Program: No such file or directory
/bin/sh: /cygdrive/c/Program: No such file or directory
/bin/sh: /cygdrive/c/Program: No such file or directory
/bin/sh: /cygdrive/c/Program: No such file or directory
/bin/sh: /cygdrive/c/Program: No such file or directory
/bin/sh: /cygdrive/c/Program: No such file or directory
/bin/sh: /cygdrive/c/Program: No such file or directory
/bin/sh: /cygdrive/c/Program: No such file or directory
PYTHON=/cygdrive/c/Program Files/Python38/python

To make things weirder we define this code twice:
First here

julia/Make.inc

Line 120 in 1524466

PYTHON := "$(shell which python 2>/dev/null || which python3 2>/dev/null || which python2 2>/dev/null || echo "{python|python3|python2} not found")"

where we still wrap it in "

cc: @staticfloat