Travis: Combine PPC/Arm tests with jpeg-7/8 tests

There is no reason not to, since the jpeg-7 and jpeg-8 API/ABI tests do
not exercise the SIMD extensions any differently than the other tests.

.travis.yml

@@ -34,22 +34,16 @@ matrix:
         CTEST_OUTPUT_ON_FAILURE=1
     - os: linux
       compiler: gcc
+      arch: ppc64le
       env:
         CMAKE_FLAGS="-DWITH_JPEG7=1"
         CTEST_OUTPUT_ON_FAILURE=1
-      addons:
-        apt:
-          packages:
-            - nasm
     - os: linux
       compiler: gcc
+      arch: arm64
       env:
         CMAKE_FLAGS="-DWITH_JPEG8=1"
         CTEST_OUTPUT_ON_FAILURE=1
-      addons:
-        apt:
-          packages:
-            - nasm
     - os: linux
       compiler: clang
       env:
@@ -57,16 +51,6 @@ matrix:
         CFLAGS_RELWITHDEBINFO="-O3 -g -fsanitize=memory -fPIE"
         CMAKE_FLAGS="-DWITH_SIMD=0"
         CTEST_OUTPUT_ON_FAILURE=1
-    - os: linux
-      compiler: gcc
-      arch: arm64
-      env:
-        CTEST_OUTPUT_ON_FAILURE=1
-    - os: linux
-      compiler: gcc
-      arch: ppc64le
-      env:
-        CTEST_OUTPUT_ON_FAILURE=1
 
 before_install:
   - if [ "$TRAVIS_OS_NAME" = "osx" ]; then