The AC_CHECK_LIB test runs unconditionally, and fails with DPDK 18.11
when built with Meson as there is no longer a libdpdk.so linker script,
but only a pkg-config file, so -ldpdk (which is what AC_CHECK_LIB runs)
fails.
Use AC_LINK_IFELSE instead, with compiler and linker flags set
appropriately.