JIT: Use vmla.f64 instead of vmuld + vaddd.

Optimize Java double floating-point performance for ARM JIT.
Whenever a double mul is followed with a double add,
replace it with a combined mul and add instruction.

This improves double arithmetic performance for code executing
in Dalvik.

Change-Id: Ia4fccf4fa53aa9fb4a76cbf388f5ea16dcef32b7
Signed-off-by: Patrik Ryd <patrik.ryd@stericsson.com>