tests: posix: xsi_realtime: bump min_ram to 96k

The xsi_realtime testsuite now includes tests for fsync() and
fdatasync() which require a ram-based fat filesystem.

Technically speaking, it would probably not be 100% necessary
to use a ramdisk to test these functions, but then the test
would be limited to running on platforms with some file-system
based storage.

Signed-off-by: Chris Friedt <[email protected]>

Author: cfriedt

tests/posix/xsi_realtime/testcase.yaml

@@ -8,8 +8,7 @@ common:
     - arch
     - simulation
   min_flash: 64
-  min_ram: 32
-  timeout: 240
+  min_ram: 96
   platform_exclude:
     # linker_zephyr_pre0.cmd:140: syntax error (??)
     - qemu_xtensa/dc233c