databases/mariadb55-server: Security update to 5.5.60

• Fix build with aarch64 [1]
• Remove new ${name}_limits behavior from 11-STABLE [2]

PR: 227628 [1], 227434 [2]
Submitted by: Naram Qashat <cyberbotx cyberbotx com> [1], 0mp [2]
MFH: 2018Q2
Security: 57aec168-453e-11e8-8777-b499baebfeaf