argon2: fix lib path for Linuxbrew
argon2: fix lib path for Linuxbrew

else their makefile will put the .so files in lib/x86_64-linux-gnu

Closes #14255.

Signed-off-by: Michka Popoff <7b0496f66f66ee22a38826c310c38b415671b832@gmail>

rwhogg/homebrew-core,rwhogg/homebrew-core,Linuxbrew/homebrew-core,LinuxbrewTestBot/homebrew-core,Linuxbrew/homebrew-core,maxim-belkin/homebrew-core,maxim-belkin/homebrew-core,LinuxbrewTestBot/homebrew-core