s390: put expoline execute-trampolines into .text section

Currently none of the vmlinux linker script patterns in .text section
match expoline execute-trampolines, and they end up as separate
sections:
.text.__s390_indirect_jump_r1,
.text.__s390x_indirect_jump_r1use_r9,
.text.__s390x_indirect_branch_4_1use_6, ...

Add a pattern to match them all.

Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>