Correct description of BN_mask_bits

CLA: trivial

Correct right shift to left shift.
Pseudo code `a&=~((~0)>>n)` means "get higher n-bits of a", but actually crypto lib gives lower n-bits.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/12727)

diff --git a/doc/man3/BN_set_bit.pod b/doc/man3/BN_set_bit.pod
index c2bed68d91e90d7f2b829946f2c893b42f5e1806..349ef9e0562cc39426685445cf7552d2c1653a47 100644 (file)
--- a/doc/man3/BN_set_bit.pod
+++ b/doc/man3/BN_set_bit.pod
@@ -33,7 +33,7 @@ error occurs if B<a> is shorter than B<n> bits.
 BN_is_bit_set() tests if bit B<n> in B<a> is set.
 
 BN_mask_bits() truncates B<a> to an B<n> bit number
-(C<a&=~((~0)E<gt>E<gt>n)>).  An error occurs if B<a> already is
+(C<a&=~((~0)E<lt>E<lt>n)>).  An error occurs if B<a> already is
 shorter than B<n> bits.
 
 BN_lshift() shifts B<a> left by B<n> bits and places the result in