SSE2: don't use VEX prefix.

Makefile

@@ -16,6 +16,7 @@ CFLAGS += -pipe
 CFLAGS += -Wall
 CFLAGS += -O2
 SIMD_CFLAGS += -mavx
+SIMD_CFLAGS += -mno-sse2avx
 SIMD_CFLAGS += -mssse3
 SIMD_CFLAGS += -funroll-loops
 CPPFLAGS += -D_GNU_SOURCE

blur.h

@@ -7,9 +7,10 @@
 void blur_image_surface (cairo_surface_t *surface, int radius);
 void blur_impl_naive(uint32_t* src, uint32_t* dst, int width, int height, int src_stride, int dst_stride, int radius);
 
+__attribute__((__target__(("no-avx"))))
 void blur_impl_sse2(uint32_t* src, uint32_t* dst, int width, int height, float sigma);
-void blur_impl_horizontal_pass_sse2(uint32_t *src, uint32_t *dst, float *kernel, int width, int height)
+__attribute__((__target__(("no-avx"))))
-    __attribute__ ((__target__ ("no-avx")));
+void blur_impl_horizontal_pass_sse2(uint32_t *src, uint32_t *dst, float *kernel, int width, int height);
 
 void blur_impl_avx(uint32_t* src, uint32_t* dst, int width, int height, float sigma);
 void blur_impl_horizontal_pass_avx(uint32_t *src, uint32_t *dst, float *kernel, int width, int height);