arch: riscv: core: vector_table alignement fix

For RISCV vector table needs to be aligned depending on
CONFIG_ARCH_IRQ_VECTOR_TABLE_ALIGN. This was missing
when using LTO making issues when direct ISR were in use.

Signed-off-by: Łukasz Stępnicki <lukasz.stepnicki@nordicsemi.no>

arch/riscv/core/vector_table.ld

@@ -6,6 +6,7 @@
 
 #if LINKER_ZEPHYR_FINAL && defined(CONFIG_ISR_TABLES_LOCAL_DECLARATION)
 KEEP(*(.vectors.__start))
+. = ALIGN(CONFIG_ARCH_IRQ_VECTOR_TABLE_ALIGN);
 INCLUDE isr_tables_vt.ld
 #else
 KEEP(*(.vectors.*))