Support passing -fPIC to all packages dependent on shared packages

[waruqi]

package()
    on_install(package)
        if package:config("pic") then -- enabled by default
           -- ..
        end
    end

We can also disable pic manually.

add_requires("xxx", {configs = {pic = false}})

Or rewrite depconfigs, see #1178

add_requireconfs("libwebp.**|cmake",   {configs = {pic = false}})

[waruqi]

#1175

[waruqi]

we need improve package deps first. #1178