[vector] RFR: Add missing @ForceInline on public API methods

[Vladimir Ivanov]

http://cr.openjdk.java.net/~vlivanov/panama/vector/inline/webrev.00/

Some public API methods miss @ForceInline annotaiton.

It can lead to significant performance degradations (due to additional 
complications for vector box elimination).

Testing: jdk/incubator/vector tests

The patch is against vectorIntrinsics branch.

Best regards,
Vladimir Ivanov