misc: allow explicitelly setting CLANG_FORMAT_VER
misc: allow explicitelly setting CLANG_FORMAT_VER

Type: improvement
Change-Id: I356b1b1804a2b09b25f5a285ada12db6879e2f6a
Signed-off-by: Damjan Marion <9141bba8b2efed526e55cf796d48631af330ad98@cisco.com>

chrisy/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,FDio/vpp,FDio/vpp,FDio/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp,chrisy/vpp,chrisy/vpp,FDio/vpp