internal/rosa: patch library paths

This removes the need for reference LDFLAGS in the standard toolchain.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/python.go

@@ -39,6 +39,10 @@ func (t Toolchain) NewPython() pkg.Artifact {
 		t.NewLibffi(),
 	}, nil, []string{
 		"EXTRATESTOPTS=-j0 -x " + strings.Join(skipTests, " -x "),
+
+		// _ctypes appears to infer something from the linker name
+		"LDFLAGS=-Wl,--dynamic-linker=/system/lib/" +
+			"ld-musl-" + linuxArch() + ".so.1",
 	}, `
 # test_synopsis_sourceless assumes this is writable and checks __pycache__
 chmod -R +w /usr/src/python/