[gdb/symtab] Don't complain about inlined functions

[gdb/symtab] Don't complain about inlined functions

With the test-case included in this patch, we get:
...
(gdb) ptype main^M
During symbol reading: cannot get low and high bounds for subprogram DIE \
  at 0x113^M
During symbol reading: cannot get low and high bounds for subprogram DIE \
  at 0x11f^M
type = int (void)^M
(gdb) FAIL: gdb.dwarf2/inline.exp: ptype main
...

The complaints are about foo, with DW_AT_inline == DW_INL_inlined:
...
 <1><11f>: Abbrev Number: 6 (DW_TAG_subprogram)
    <120>   DW_AT_name        : foo
    <126>   DW_AT_prototyped  : 1
    <126>   DW_AT_type        : <0x10c>
    <12a>   DW_AT_inline      : 1       (inlined)
...
and foo2, with DW_AT_inline == DW_INL_declared_inlined:
...
 <1><113>: Abbrev Number: 5 (DW_TAG_subprogram)
    <114>   DW_AT_name        : foo2
    <11a>   DW_AT_prototyped  : 1
    <11a>   DW_AT_type        : <0x10c>
    <11e>   DW_AT_inline      : 3       (declared as inline and inlined)
...

Fix this by not complaining about inlined functions.

Tested on x86_64-linux.