Adjust the output section size to skip gap fills

Adjust the output section size to skip gap fills

In objcopy, copy_object calls copy_section to copy contents of input
section to output section.  When --gap-fill= is used, objcopy extends
the size of output sectios to fill gaps between output sections with
gap fills.  In this case, we adjust the output section size to skip
gap files to avoid reading beypond the input section buffer before
calling copy_section and restore the output section size after input
sections have been copied.

binutils/

	PR binutils/19005
	* objcopy.c (copy_object): Adjust the output section size to
	skip gap fills between sections when copying from input sections
	to output sections.

ld/testsuite/

	PR binutils/19005
	* ld-elf/pr19005.d: New file.
	* ld-elf/pr19005.s: Likewise.
	* ld-elf/pr19005.t: Likewise.