[texdoc] l3color doc

[Pablo González L]

Hello, the output of $texdoc -l l3color
 1 /usr/local/texlive/2019/texmf-dist/doc/latex/l3kernel/interface3.pdf
   = The LaTeX3 interfaces
 2 /usr/local/texlive/2019/texmf-dist/doc/latex/l3experimental/l3color/l3color.pdf
   = l3color documentation
should be
 1 /usr/local/texlive/2019/texmf-dist/doc/latex/l3experimental/l3color/l3color.pdf
   = l3color documentation
 2 /usr/local/texlive/2019/texmf-dist/doc/latex/l3experimental/l3color/l3color-code.pdf