fix vc_copylineRG48toY216

incorrectly braced

Actually not obvious until 2f45006 (2024-09-24) because the chroma x1.5
was used but clamped, which has somehow hidden that.

src/pixfmt_conv.c

@@ -2365,6 +2365,7 @@ static void vc_copylineRG48toV210(unsigned char * __restrict dst, const unsigned
 #undef FETCH_BLOCK
 }
 
+
 static void vc_copylineRG48toY216(unsigned char * __restrict dst, const unsigned char * __restrict src, int dst_len, int rshift,
                 int gshift, int bshift) {
         enum {
@@ -2392,14 +2393,14 @@ static void vc_copylineRG48toY216(unsigned char * __restrict dst, const unsigned
                 r = *in++;
                 g = *in++;
                 b = *in++;
-                u = (u + (RGB_TO_CB(cfs, r, g, b) >> COMP_BASE) /
+                u = ((u + (RGB_TO_CB(cfs, r, g, b) >> COMP_BASE)) /
                              2) +
                     (1 << 15);
                 *d++ = CLAMP_LIMITED_CBCR(u, 16);
                 y    = (RGB_TO_Y(cfs, r, g, b) >> COMP_BASE) +
                     (1 << 12);
                 *d++ = CLAMP_LIMITED_Y(y, 16);
-                v = (v + (RGB_TO_CR(cfs, r, g, b) >> COMP_BASE) /
+                v = ((v + (RGB_TO_CR(cfs, r, g, b) >> COMP_BASE)) /
                              2) +
                     (1 << 15);
                 *d++ = CLAMP_LIMITED_CBCR(v, 16);