use qemu_memalign for all cpu structs

Some structs, specically CPUARMState is 16-bytes aligned.

This causes segment fault because gcc tends to vectorize

the assignment of the struct with infamous movaps tricks.

Without this patch, we fail on manylinux with 2.17 glibc

in release mode in i686.

qemu_memalign will ensure the alignment across platforms.

uc.c

@@ -515,7 +515,7 @@ uc_err uc_close(uc_engine *uc)
     g_free(uc->cpu->thread);
 
     /* cpu */
-    free(uc->cpu);
+    qemu_vfree(uc->cpu);
 
     /* flatviews */
     g_hash_table_destroy(uc->flat_views);