libsframe: rename API sframe_fde_func_info to sframe_fde_create_func_info

The new name better reflects the purpose of the function.

ChangeLog:

	* bfd/elfxx-x86.c (_bfd_x86_elf_create_sframe_plt): Use new
	name.
	* libsframe/sframe.c (sframe_fde_create_func_info): Rename
	sframe_fde_func_info to this.
	* libsframe/testsuite/libsframe.encode/encode-1.c: Use new name.

include/ChangeLog:

	* sframe-api.h (sframe_fde_create_func_info): Rename
	sframe_fde_func_info to this.