[BUG] Support for GCC15

[raiden00pl]

Description / Steps to reproduce the issue

New version of GCC and new problems :)

Not solved problems from #12436 (GCC14):

• drivers/clk/clk.h:xx:5: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
• drivers/video/v4l2_cap.c:798:3: error: pointer/integer type mismatch in conditional expression [-Wint-conversion]
• include/nuttx/spi/spi_bitbang.c
  Support for GCC14 #12436 (comment)

New problems in GCC15:

• warnings in sim/smp
• sim/nimble doesn't compile
• CONFIG_LIBCXX=y does't compile
• ...

On which OS does this issue occur?

[OS: Linux]

What is the version of your OS?

doesn't matter

NuttX Version

master

Issue Architecture

[Arch: all]

Issue Area

[Area: Kernel]

Host information

No response

Verification

• I have verified before submitting the report.