Pass arch to the qemu wrapper script.

   * Since we are using the same same qemu wrapper script (module_wrapper script)
     pass the architecture to it.  The wrapper in main repo will invoke
     the right qemu binary based on the architecture.

   * Kernel args have spaces in betwen. To keep it simple pass kernel args
     separately to the wrapper script and before invoking the qemu binary
     pass each of the needed args.

bazel/linux/qemu.bzl

@@ -48,7 +48,6 @@ test -n "$QEMU_BINARY" || {{
 }}
 
 if [[ "$ARCH" == "x86" ]]; then
-
     if [ -n "$ROOTFS" ]; then
         QEMU_FLAGS+=("-drive" "file=$ROOTFS,if=virtio,cache=none")
     else
@@ -63,8 +62,6 @@ if [[ "$ARCH" == "x86" ]]; then
 
     test -z "$KERNEL" || QEMU_FLAGS+=("-kernel" "$KERNEL")
     test -z "$SINGLE" || KERNEL_FLAGS+=("init=/bin/sh")
-
-    QEMU_FLAGS+=("-append" "${{KERNEL_FLAGS[*]}} ${{KERNEL_OPTS[*]}}")
 fi
 
 if [[ "$ARCH" == "aarch64" ]] ; then
@@ -79,22 +76,21 @@ if [[ "$ARCH" == "aarch64" ]] ; then
     echo "QEMU_FLAGS: $QEMU_FLAGS"
 fi
 
+WRAPPER_OPTS+="arch=$ARCH"
+
 QEMU_FLAGS+=("${{EMULATOR_OPTS[@]}}")
 
 if [ ${{#WRAPPER_OPTS[@]}} -ne 0 ]; then
     WRAPPER_OPTS=('--' "${{WRAPPER_OPTS[@]}}")
 fi
 
+# Pass qemu/kernel/wrapper opts as three separate args to Qemu binary.
+
 echo 1>&2 '$' "$QEMU_BINARY" "${{QEMU_FLAGS[@]}}" "${{WRAPPER_OPTS[@]}}"
 if [ -z "$INTERACTIVE" -a -z "$SINGLE" ]; then
-    "$QEMU_BINARY" "${{QEMU_FLAGS[@]}}" "${{WRAPPER_OPTS[@]}}" </dev/null | tee "$OUTPUT_FILE"
+    "$QEMU_BINARY" "${{QEMU_FLAGS[*]}}"  "${{KERNEL_FLAGS[*]}}" "${{WRAPPER_OPTS[*]}}" </dev/null | tee "$OUTPUT_FILE"
 else
-  if [[ "$ARCH" == "aarch64" ]]; then
-      CMD="$QEMU_BINARY ${{QEMU_FLAGS[@]}} ${{WRAPPER_OPTS[@]}}"
-      $CMD
-  else
-     "$QEMU_BINARY" "${{QEMU_FLAGS[@]}}" "${{WRAPPER_OPTS[@]}}"
-  fi
+    "$QEMU_BINARY" "${{QEMU_FLAGS[*]}}" "${{KERNEL_FLAGS[*]}}" "${{WRAPPER_OPTS[*]}}"
 fi
 """
     qemu_search = ctx.attr.qemu_search
@@ -106,6 +102,7 @@ fi
     qemu_flags = ctx.attr.qemu_defaults + ctx.attr.qemu_flags
 
     if "aarch64" in ctx.attr.archs:
+       # no cmdline kernel flags for aarch64 qemu.  All embeded in the fit image for now
        arch = "aarch64"
        kernel_flags = []
     else: