Fix "FAIL: check-system-flags"
pkg-config strips system include and lib.
For passing the test, enable system include and lib by appending PKG_CONFIG_ALLOW_SYSTEM_CFLAGS and PKG_CONFIG_ALLOW_SYSTEM_LIBS environment variable.
Related #51.
pkg-config strips system include and lib.
For passing the test, enable system include and lib by appending PKG_CONFIG_ALLOW_SYSTEM_CFLAGS and PKG_CONFIG_ALLOW_SYSTEM_LIBS environment variable.
Related #51.