Merge commit '9d5c62ba5b586c80af508b5914934b1c439f6652'

* commit '9d5c62ba5b586c80af508b5914934b1c439f6652':
  lavu/opt: do not filter out the initial sign character except for flags
  eval: treat dB as decibels instead of decibytes
  float_dsp: add vector_dmul_scalar() to multiply a vector of doubles

Conflicts:
	libavutil/eval.c
	tests/ref/fate/eval

Merged-by: Michael Niedermayer <michaelni@gmx.at>

tests/ref/fate/eval

@@ -184,6 +184,12 @@ Evaluating 'not(NAN)'
 Evaluating 'not(0)'
 'not(0)' -> 1.000000
 
+Evaluating '6.0206dB'
+'6.0206dB' -> 2.000000
+
+Evaluating '-3.0103dB'
+'-3.0103dB' -> 0.707107
+
 Evaluating 'pow(0,1.23)'
 'pow(0,1.23)' -> 0.000000