add infcall_mmap and gcc_target_options gdbarch methods

add infcall_mmap and gcc_target_options gdbarch methods

The compiler needed two new gdbarch methods.

The infcall_mmap method allocates memory in the inferior.
This is used when inserting the object code.

The gcc_target_options method computes some arch-specific gcc options
to pass to the compiler.  This is used to ensure that gcc generates
object code for the correct architecture.

gdb/ChangeLog
2014-12-12  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* arch-utils.c (default_infcall_mmap)
	(default_gcc_target_options): New functions.
	* arch-utils.h (GDB_MMAP_PROT_READ, GDB_MMAP_PROT_WRITE)
	(GDB_MMAP_PROT_EXEC): Define.
	(default_infcall_mmap, default_gcc_target_options): Declare.
	* gdbarch.h: Rebuild.
	* gdbarch.c: Rebuild.
	* gdbarch.sh (infcall_mmap, gcc_target_options): New methods.