All cores which add a cpu_addrcost_table use a non-zero value for

All cores which add a cpu_addrcost_table use a non-zero value for
HI and TI mode shifts (a non-zero value for general indexing also
applies to all shifts).  Given this, it makes no sense to use a
different setting in generic_addrcost_table.  So change it so that
all supported cores, including -mcpu=generic, now generate the same:

int f(short *p, short *q, long x) { return p[x] + q[x]; }

        lsl     x2, x2, 1
        ldrsh   w3, [x0, x2]
        ldrsh   w0, [x1, x2]
        add     w0, w3, w0
        ret

    gcc/
	* config/aarch64/aarch64.c (generic_addrcost_table):
	Change HI/TI mode setting.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@247606 138bc75d-0d04-0410-961f-82ee72b054a4