highbd_variance_avx2.c: fix #undef

this was missed in:
f2658a3cfe clear -Wextra-semi/-Wextra-semi-stmt warnings

SSE2_Height -> SSE2_HEIGHT

Change-Id: I728628bcb995cc90c9f7a2c1382b7f047653fb2c

aom_dsp/x86/highbd_variance_avx2.c

diff --git a/aom_dsp/x86/highbd_variance_avx2.c b/aom_dsp/x86/highbd_variance_avx2.c
index c39c238..adbb736 100644
--- a/aom_dsp/x86/highbd_variance_avx2.c
+++ b/aom_dsp/x86/highbd_variance_avx2.c
@@ -749,7 +749,7 @@
 SSE2_HEIGHT(8)
 SSE2_HEIGHT(16)
 
-#undef SSE2_Height
+#undef SSE2_HEIGHT
 
 #define HIGHBD_SUBPIX_VAR(W, H)                                              \
   uint32_t aom_highbd_10_sub_pixel_variance##W##x##H##_avx2(                 \