[X4][202511] Add support for IXR7250 X4 platform

[fzhou-nokia]

Add support for NOKIA 7250-IXR-X4 platform in 202511 Branch:

Platform: x86_64-nokia_ixr7250_x4-r0
HwSKU: Nokia-IXR7250-X4
ASIC: Broadcom
Port Config: 32x800G

How I did it

1. Add platform related directory ixr7250x4 in platform/Broadcom/sonic-platform-modules-nokia
2. Modified related build scripts in platform/Broadcom/sonic-platform-modules-nokia/debian

How to verify it

1. Make sure the sonic-buildimage is successful
2. Run this image on x86_64-nokia_ixr7250_x4-r0 and verify all dockers are up and test basic commands like:

• show version
• show platform summary
• show platform syseeprom
• show platform fan
• show platform psustatus
• show platform firmware status
• show platform temperature
• sudo show system-health detail
• show interface status

3. Run OC test and have 100% pass on platform.