common/cnxk: remove dead Meson code

[ upstream commit 9b99bf003793fe3e2108ea8f2fdef555542730d9 ]

config_flag_fmt was used in the past and was dropped with commit
762bfcc ("config: remove compatibility build defines").

Fixes: fa8f86a ("common/cnxk: add build infrastructre and HW definition")

Signed-off-by: David Marchand <david.marchand@redhat.com>

drivers/common/cnxk/meson.build

@@ -8,7 +8,6 @@ if not is_linux or not dpdk_conf.get('RTE_ARCH_64')
     subdir_done()
 endif
 
-config_flag_fmt = 'RTE_LIBRTE_@0@_COMMON'
 deps = ['eal', 'pci', 'bus_pci', 'mbuf', 'security']
 sources = files(
         'roc_ae.c',