Update the F1 messages and build scripts for proper generation of F1 messages

.gitignore

cmake_targets/CMakeLists.txt

cmake_targets/build_oai

cmake_targets/tools/build_helper

cmake_targets/tools/fix_asn1

openair2/F1AP/MESSAGES/ASN1/R15.1.1/F1AP-CommonDataTypes.asn

openair2/F1AP/MESSAGES/ASN1/R15.1.1/F1AP-Constants.asn

openair2/F1AP/MESSAGES/ASN1/R15.1.1/F1AP-Containers.asn

openair2/F1AP/MESSAGES/ASN1/R15.1.1/F1AP-IEs.asn

openair2/F1AP/MESSAGES/ASN1/R15.1.1/F1AP-PDU-Contents.asn

...air2/F1AP/MESSAGES/ASN1/R15.1.1/F1AP-PDU-Descriptions.asn

openair2/F1AP/MESSAGES/ASN1/R15.1.1/asn1_constants.h

openair2/F1AP/MESSAGES/ASN1/asn1tostruct.py