CMake: Set correct assembler for MSVC ARM targets

[Greenie0701]

Description:

• The existing configuration sets the assembly language to ASM_ARMASM for BOOST_CONTEXT_ASSEMBLER for all arm compilers.
• This patch introduces a conditional check for MSVC to set the assembly language to ASM_MARMASM instead.

Changes:

• Added a conditional statement to check if the compiler is MSVC.
• Set ASM_LANGUAGE to ASM_MARMASM if MSVC is detected.
• Retained the existing setting of ASM_ARMASM for non-MSVC compilers.

[olk]

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