[emacs support] add a missing (require 'compile)

Author: Dave Abrahams

utils/swift-project-settings.el

@@ -239,6 +239,7 @@ takes precedence for files in the Swift project"
         ad-do-it)
     ad-do-it))
 
+(require 'compile) ;; for compilation-error-regexp-alist et al.
 (push 'swift-stdlibunittest-possibly-expected-assertion compilation-error-regexp-alist)
 (push `(swift-stdlibunittest-possibly-expected-assertion "^\\(\\(?:stdout\\|stderr\\)>>> *\\)?.*\\(?:failed\\(?: at\\|.*file\\)\\|.*: file\\) \\([^,]*\\), line \\([0-9]+\\)$"
               2 3 ,(not :column) 0)