Fixed stupid endianness bug.

Incorrect endianness hilariously doesn't manifest _if_ the original
image was upconverted from 8-bit to 16-bit.

stb_image.h

@@ -5195,7 +5195,7 @@ static stbi_uc *stbi__psd_load(stbi__context *s, int *x, int *y, int *comp, int
             // Read the data.
             if (bitdepth == 16) {
                for (i = 0; i < pixelCount; i++, p += 4)
-                  *p = stbi__get16le(s) * 255 / 65535;
+                  *p = stbi__get16be(s) * 255 / 65535;
             } else {
                for (i = 0; i < pixelCount; i++, p += 4)
                   *p = stbi__get8(s);