Fix build issue with new error checks.

rs_allocation gIn;

float gCoeffs[9];

void setCoefficients(float coef[9]) {

    for(int i=0; i < 9; i++) {

        gCoeffs[i] = coef[i];

    }

}

void root(uchar4 *out, uint32_t x, uint32_t y) {

    uint32_t x1 = min((int32_t)x+1, gWidth);