Fix typos in symtab_symbol_info

Fix typos in symtab_symbol_info

symtab_symbol_info has a couple of messages that say "regulation
expression".  I think "regular expression" was meant, so this patch
changes it.

gdb/ChangeLog
2019-02-20  Tom Tromey  <tom@tromey.com>

	* symtab.c (symtab_symbol_info): Fix typos.

gdb/testsuite/ChangeLog
2019-02-20  Tom Tromey  <tom@tromey.com>

	* gdb.base/info_qt.exp: Update.