travis: Drop redundant DPDK build check.
This check covered by 'TESTSUITE=1 DPDK=1'.
No need to run it separately.
@@ -33,7 +33,6 @@ env:
- TESTSUITE=1 KERNEL=3.16.54
- TESTSUITE=1 OPTS="--enable-shared"
- BUILD_ENV="-m32" OPTS="--disable-ssl"
- - KERNEL=3.16.54 DPDK=1
- KERNEL=3.16.54 DPDK=1 OPTS="--enable-shared"
- KERNEL=3.16.54 TESTSUITE=1 DPDK=1
- KERNEL=3.16.54 DPDK_SHARED=1
