drm/amd/display: dont subst v without RISCV_ISA_V

Prevent v in rv64 to be removed by subst.

Signed-off-by: Yukari Chiba <[email protected]>

Author: YukariChiba

drivers/gpu/drm/amd/display/dc/dml/Makefile

@@ -45,8 +45,12 @@ endif
 
 ifdef CONFIG_RISCV
 include $(srctree)/arch/riscv/Makefile.isa
+ifdef CONFIG_RISCV_ISA_V
 # Remove V from the ISA string, like in arch/riscv/Makefile, but keep F and D.
 dml_ccflags := -march=$(subst v,,$(riscv-march-y))
+else
+dml_ccflags := -march=$(riscv-march-y)
+endif
 endif
 
 ifdef CONFIG_CC_IS_GCC