tests: fs: fat_fs_api: Add NXP platforms for filesystem.fat.ram.api

- Adds NXP platforms for the filesystem.fat.ram.api test case.
- Renames prj_native_ram.conf to prj_ram.conf,
  as it can be used by all platforms.

Signed-off-by: Andrej Butok <andrey.butok@nxp.com>

tests/subsys/fs/fat_fs_api/testcase.yaml

@@ -20,9 +20,30 @@ tests:
     filter: dt_compat_enabled("zephyr,sdmmc-disk")
   filesystem.fat.ram.api:
     platform_allow:
+      - frdm_mcxa156
+      - frdm_mcxn236
+      - frdm_mcxn947/mcxn947/cpu0
+      - frdm_mcxw71
+      - frdm_rw612
+      - lpcxpresso55s06
+      - lpcxpresso55s28
+      - lpcxpresso55s36
+      - lpcxpresso55s69/lpc55s69/cpu0
+      - mimxrt1020_evk
+      - mimxrt1024_evk
+      - mimxrt1040_evk
+      - mimxrt1050_evk/mimxrt1052/hyperflash
+      - mimxrt1060_evk/mimxrt1062/qspi
+      - mimxrt1064_evk
+      - mimxrt1160_evk/mimxrt1166/cm7
+      - mimxrt1170_evk/mimxrt1176/cm7
+      - mimxrt1180_evk/mimxrt1189/cm33
+      - mimxrt595_evk/mimxrt595s/cm33
+      - mimxrt685_evk/mimxrt685s/cm33
+    integration_platforms:
       - native_sim
     extra_args:
-      - CONF_FILE="prj_native_ram.conf"
+      - CONF_FILE="prj_ram.conf"
       - EXTRA_DTC_OVERLAY_FILE="ramdisk.overlay"
   filesystem.fat.api.reentrant:
     platform_allow: