env/darwin/aws: don't quote extra args

We do not want to quote $EXTRA_ARGS, as we explicitly want them split
into multiple arguments to qemu. This fixes start-installer.sh.

For golang/go#48945.

Change-Id: I6659f74120be534e9d909bcff85151011f8addd2
Reviewed-on: https://go-review.googlesource.com/c/build/+/432856
Run-TryBot: Michael Pratt <[email protected]>
Reviewed-by: Heschi Kreinick <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>

Author: prattmic

env/darwin/aws/qemu.sh

@@ -43,4 +43,4 @@ args=(
   -display vnc=127.0.0.1:"$PORT"
 )
 
-DYLD_LIBRARY_PATH="$HOME/sysroot-macos-x86_64/lib" "$HOME/sysroot-macos-x86_64/bin/qemu-system-x86_64" "${args[@]}" ${EXTRA_ARGS:+"$EXTRA_ARGS"}
+DYLD_LIBRARY_PATH="$HOME/sysroot-macos-x86_64/lib" "$HOME/sysroot-macos-x86_64/bin/qemu-system-x86_64" "${args[@]}" ${EXTRA_ARGS:+$EXTRA_ARGS}