PRU: Allow device spec to append assembler command line.
The PRU target now allows appending assembler command-line options using the device spec.
The PRU (Programmable Real-time Unit) target in GCC now supports appending assembler command-line options through the device spec. This functionality allows specifying PRU core revisions via the asm_device spec variable, providing a consistent approach similar to how linker and C preprocessor device-specific variables are handled.
In Details
This commit adds ASM_SPEC to config/pru/pru.h, enabling the use of asm_device to append assembler command-line options. This mirrors the existing functionality for linker and C preprocessor device specifications.
For Context
This commit modifies the GCC compiler to allow specifying additional options to the assembler when compiling code for the PRU (Programmable Real-time Unit). The PRU is a specialized microcontroller often used in embedded systems for real-time tasks. This change enables developers to fine-tune the assembly process for specific PRU hardware configurations.