Replace psymbol_allocation_list with std::vector

psymbol_allocation_list is basically a vector implementation.  We can
replace it with an std::vector, now that objfile has been C++-ified.

I sent this to the buildbot, there are a few suspicious failures, but
I don't think they are related to this patch.  For example on powerpc:

new FAIL: gdb.base/catch-syscall.exp: execve: syscall execve has returned
new FAIL: gdb.base/catch-syscall.exp: execve: continue to main
new FAIL: gdb.base/catch-syscall.exp: execve: continue until exit

I get the same failures when testing manually on gcc112, without this
patch.

gdb/ChangeLog:

	* objfiles.h: Don't include symfile.h.
	(struct partial_symbol): Remove forward-declaration.
	(struct objfile) <global_psymbols, static_psymbols>: Change type
	to std::vector<partial_symbol *>.
	* objfiles.c (objfile::objfile): Don't memset those fields.
	(objfile::~objfile): Don't free those fields.
	* psympriv.h (struct psymbol_allocation_list): Remove
	forward-declaration.
	(add_psymbol_to_list): Change psymbol_allocation_list parameter
	to std::vector.
	(start_psymtab_common): Change parameters to std::vector.
	* psymtab.c: Include algorithm.
	(require_partial_symbols): Call shrink_to_fit.
	(find_pc_sect_psymbol): Adjust to vector change.
	(match_partial_symbol): Likewise.
	(lookup_partial_symbol): Likewise.
	(psym_relocate): Likewise.
	(dump_psymtab): Likewise.
	(recursively_search_psymtabs): Likewise.
	(compare_psymbols): Remove.
	(sort_pst_symbols): Adjust to vector change.
	(start_psymtab_common): Likewise.
	(end_psymtab_common): Likewise.
	(psymbol_bcache_full): De-constify return value.
	(add_psymbol_to_bcache): Likewise.
	(extend_psymbol_list): Remove.
	(append_psymbol_to_list): Adjust to vector change.
	(add_psymbol_to_list): Likewise.
	(init_psymbol_list): Likewise.
	(maintenance_info_psymtabs): Likewise.
	(maintenance_check_psymtabs): Likewise.
	* symfile.h (struct psymbol_allocation_list): Remove.
	* symfile.c (reread_symbols): Adjust to vector change.
	* dbxread.c (start_psymtab): Change type of parameters.
	(dbx_symfile_read): Adjust to vector change.
	(read_dbx_symtab): Likewise.
	(start_psymtab): Change type of parameters.
	* dwarf2read.c (dwarf2_build_psymtabs): Adjust to vector change.
	(create_partial_symtab): Likewise.
	(add_partial_symbol): Likewise.
	(write_one_signatured_type): Likewise.
	(recursively_write_psymbols): Likewise.
	* mdebugread.c (parse_partial_symbols): Likewise.
	* xcoffread.c (xcoff_start_psymtab): Change type of parameters.
	(scan_xcoff_symtab): Adjust to vector change.
	(xcoff_initial_scan): Likewise.