refactor(core): Simplify setBufPos in ua_securechannel_crypto.c
refactor(core): Simplify setBufPos in ua_securechannel_crypto.c

StalderT/open62541,open62541/open62541,open62541/open62541,JGrothoff/open62541,jpfr/open62541,jpfr/open62541,jpfr/open62541,JGrothoff/open62541,StalderT/open62541,StalderT/open62541,StalderT/open62541,jpfr/open62541,open62541/open62541,JGrothoff/open62541,JGrothoff/open62541,open62541/open62541