build file lacks install directives for shared object

[falconindy]

In the default configuration, building fmt from the wrapped build produces a shared object which is never installed. This means projects using the wrap work within the build tree, but are broken upon installation.

From IRC:

14:05         jpakkane@ » No, just install it as normal.
14:05         dreisner  » i'm not sure what that means in this context.
14:06         dreisner  » i can't set install:true on the subproject's lib
14:06         jpakkane@ » Exactly the same thing as in any other context. It gets installed as usual.
                          If a subproject is missing install directives, then it is buggy and needs to be fixed.
14:07         dreisner  » so this is broken? https://github.com/mesonbuild/fmt/blob/5.2.1/meson.build
14:08         jpakkane@ » Yes. It's not installed at all so it won't work when built as a shared library.

There needs to be some detection of the shared lib being built to ensure that libfmt.so is installed.

[sarum9in]

I think if you add install directive to https://github.com/mesonbuild/fmt/blob/5.2.1/meson.build it will solve the problem? Also possibly a conditional one if you prefer.