Hi,

This patch supports following -march/-mbranch-protection combination by linking them
to existing pacbti multilibs.

$ -march=armv8.1-m.main+pacbti+fp.dp+mve.fp -mbranch-protection=standard -mfloat-abi=hard -mthumb
$ -march=armv8.1-m.main+pacbti+fp.dp+mve -mbranch-protection=standard -mfloat-abi=hard -mthumb
$ -march=armv8.1-m.main+dsp+pacbti+fp.dp -mbranch-protection=standard -mfloat-abi=hard -mthumb

Regression tested on arm-none-eabi and bootstrapped on arm-none-linux-gnueabihf.

Ok for master?

Regards,
Srinath.

gcc/ChangeLog:

2022-08-12  Srinath Parvathaneni  <srinath.parvathaneni@arm.com>

        * config/arm/t-rmprofile: Add pacbti multililb variants.

gcc/testsuite/ChangeLog:

2022-08-12  Srinath Parvathaneni  <srinath.parvathaneni@arm.com>

        * gcc.target/arm/pac-10.c: New test.
        * gcc.target/arm/pac-11.c: Likewise.
        * gcc.target/arm/pac-12.c: Likewise.