This applies the second part of GDB's End of Year Procedure, which
updates the copyright year range in all of GDB's files.
gdb/ChangeLog:
Update copyright year range in all GDB files.
* symtab.c (skip_prologue_using_sal): Consider a file
change the same as an increased line number
gdb/testsuite/
* gdb.base/prologue-include.c: New file.
* gdb.base/prologue-include.exp: New file.
* gdb.base/prologue-include.h: New file.