objdump --disassemble=sym peculiarities

Given this testcase:
 .text
 mov $x1,%eax
f1:
 mov $f1,%eax
 .type f1,@function
 .size f1,.-f1

 mov $x2,%eax
f2:
 mov $f2,%eax
 .type f2,@function
 .size f2,.-f2+0x1000 #bad size

objdump --reloc --disassemble=f1 prints
00000000 <f1-0x5>:
   0:	b8 00 00 00 00       	mov    $0x0,%eax

and objdump --reloc --disassemble=f2 prints
0000000f <f2>:
   f:	b8 0f 00 00 00       	mov    $0xf,%eax
			10: R_386_32	.text

It seems for f1 we get the insn before f1 and no reloc whereas, post
159daa36, f2 is disassembled correctly.  Some analysis says that
find_symbol_for_address may return a symbol past the current address,
and reloc skipping is broken.  Fix both of these problems.

	* objdump.c (disassemble_jumps, disassemble_bytes): Replace
        relppp with relpp, ie. don't update caller's rel_pp.  Adjust
        calls.
	(disassemble_section): Skip over relocs inside loop rather
        than before loop.  Revert 7e538762.  If given a symbol,
	don't start disassembling until its address is reached.
	Correct end of function calculation.