[Bug testsuite/77635] New: load/store pair testcases need to use -mcpu=generic

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77635

            Bug ID: 77635
           Summary: load/store pair testcases need to use -mcpu=generic
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: testsuite
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---
            Target: aarch64*-*-*

When I added load/store pair word unaligned to the backend, I forgot to update
the testsuite to use -mcpu=generic so the following testcases fail currently
when gcc is configured --with-cpu=thunderx:
-FAIL: gcc.target/aarch64/ldp_stp_1.c scan-assembler-times stp\\tw[0-9]+,
w[0-9] 7
-FAIL: gcc.target/aarch64/store-pair-1.c scan-assembler stp\\tw([0-9]+)|(zr),
w[0-9]+