CMakeLists: add ppc case

Signed-off-by: Sergey Fedorov <barracuda@macos-powerpc.org>

CMakeLists.txt

@@ -81,6 +81,24 @@ elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "(ppc64|powerpc64)")
     if(${OQS_DIST_BUILD})
         set(OQS_DIST_PPC64_BUILD ON)
     endif()
+elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "(ppc|powerpc)")
+    message(WARNING "There is currently no CI for: " ${CMAKE_SYSTEM_PROCESSOR})
+    # CMake uses uname to derive CMAKE_SYSTEM_PROCESSOR value, so on Darwin
+    # the value is identical for ppc and ppc64. To have the right build arch
+    # in 64-bit case, we use CMAKE_OSX_ARCHITECTURES.
+    if(APPLE AND CMAKE_OSX_ARCHITECTURES STREQUAL "ppc64")
+        set(ARCH "ppc64")
+        set(ARCH_PPC64 ON)
+        if(${OQS_DIST_BUILD})
+            set(OQS_DIST_PPC64_BUILD ON)
+        endif()
+    else()
+        set(ARCH "ppc")
+        set(ARCH_PPC ON)
+        if(${OQS_DIST_BUILD})
+            set(OQS_DIST_PPC_BUILD ON)
+        endif()
+    endif()
 elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "s390x")
     set(ARCH "s390x")
     set(ARCH_S390X ON)