correction for mixerHex6P and mixerHex6X

hi,

imho : here are the correct mixers 

static const motorMixer_t mixerHex6P[] = {
    { 1.0f, -0.866025f,  0.5f,  1.0f },     // REAR_R
    { 1.0f, -0.866025f, -0.5f, -1.0f },     // FRONT_R
    { 1.0f,  0.866025f,  0.5f,  1.0f },     // REAR_L
    { 1.0f,  0.866025f, -0.5f, -1.0f },     // FRONT_L
    { 1.0f,  0.0f,      -1.0f,  1.0f },     // FRONT
    { 1.0f,  0.0f,       1.0f, -1.0f },     // REAR
};
static const motorMixer_t mixerHex6X[] = {
    { 1.0f, -0.5f,  0.866025f,  1.0f },     // REAR_R
    { 1.0f, -0.5f, -0.866025f,  1.0f },     // FRONT_R
    { 1.0f,  0.5f,  0.866025f, -1.0f },     // REAR_L
    { 1.0f,  0.5f, -0.866025f, -1.0f },     // FRONT_L
    { 1.0f, -1.0f,  0.0f,      -1.0f },     // RIGHT
    { 1.0f,  1.0f,  0.0f,       1.0f },     // LEFT
};

plus a minor ident issue in board.h