provider-keymgmt.pod: fix typo

Fix a typo from asymmmetric to asymmetric

CLA: trivial

Reviewed-by: Paul Yang <kaishen.yy@antfin.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from #23164)

doc/man7/provider-keymgmt.pod

@@ -376,7 +376,7 @@ length is specific to the key cryptosystem.
 
 The value should be the maximum size that a caller should allocate to
 safely store a signature (called I<sig> in L<provider-signature(7)>),
-the result of asymmmetric encryption / decryption (I<out> in
+the result of asymmetric encryption / decryption (I<out> in
 L<provider-asym_cipher(7)>, a derived secret (I<secret> in
 L<provider-keyexch(7)>, and similar data).