Remove some unnecessary undefs in bn_asm.c

This is likely the leftover of a previous hack,
and thus should be removed now.

Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from #17259)

(cherry picked from commit 17cca0e)
Reviewed-by: Hugo Landau <hlandau@openssl.org>

crypto/bn/bn_asm.c

@@ -422,11 +422,6 @@ BN_ULONG bn_sub_words(BN_ULONG *r, const BN_ULONG *a, const BN_ULONG *b,
 
 #if defined(BN_MUL_COMBA) && !defined(OPENSSL_SMALL_FOOTPRINT)
 
-# undef bn_mul_comba8
-# undef bn_mul_comba4
-# undef bn_sqr_comba8
-# undef bn_sqr_comba4
-
 /* mul_add_c(a,b,c0,c1,c2)  -- c+=a*b for three word number c=(c2,c1,c0) */
 /* mul_add_c2(a,b,c0,c1,c2) -- c+=2*a*b for three word number c=(c2,c1,c0) */
 /* sqr_add_c(a,i,c0,c1,c2)  -- c+=a[i]^2 for three word number c=(c2,c1,c0) */
@@ -950,8 +945,6 @@ int bn_mul_mont(BN_ULONG *rp, const BN_ULONG *ap, const BN_ULONG *bp,
 #else                           /* !BN_MUL_COMBA */
 
 /* hmm... is it faster just to do a multiply? */
-# undef bn_sqr_comba4
-# undef bn_sqr_comba8
 void bn_sqr_comba4(BN_ULONG *r, const BN_ULONG *a)
 {
     BN_ULONG t[8];