[gcc(refs/vendors/riscv/heads/gcc-15-with-riscv-opts)] RISC-V: Add comment and reorder the the include files in riscv.md [NFC]

[Jeff Law]

https://gcc.gnu.org/g:1c07217a77b4bde471729be74008f7f061324b9d

commit 1c07217a77b4bde471729be74008f7f061324b9d
Author: Kito Cheng <kito.cheng@sifive.com>
Date:   Thu Jun 26 14:26:57 2025 +0800

    RISC-V: Add comment and reorder the the include files in riscv.md [NFC]
    
    This patch adds a comment to the riscv.md file to clarify the purpose of
    the file and reorders the include files for better organization.
    
    gcc/ChangeLog:
    
            * config/riscv/riscv.md: Add comment and reorder include
            files.
    
    (cherry picked from commit 14035a14aac24fb60bf7bbc803d7275fc32fdcae)

Diff:
---
 gcc/config/riscv/riscv.md | 19 +++++++++++--------
 1 file changed, 11 insertions(+), 8 deletions(-)

diff --git a/gcc/config/riscv/riscv.md b/gcc/config/riscv/riscv.md
index bfacc0c82686..c5d2828bc52a 100644
--- a/gcc/config/riscv/riscv.md
+++ b/gcc/config/riscv/riscv.md
@@ -4885,6 +4885,7 @@
   { operands[3] = GEN_INT (BITS_PER_WORD
 			   - exact_log2 (INTVAL (operands[3]) + 1)); })
 
+;; Standard extensions and pattern for optimization
 (include "bitmanip.md")
 (include "crypto.md")
 (include "sync.md")
@@ -4892,19 +4893,21 @@
 (include "sync-ztso.md")
 (include "peephole.md")
 (include "pic.md")
-(include "generic.md")
-(include "sifive-7.md")
-(include "sifive-p400.md")
-(include "sifive-p600.md")
-(include "thead.md")
-(include "generic-vector-ooo.md")
-(include "generic-ooo.md")
-(include "vector.md")
 (include "vector-crypto.md")
 (include "vector-bfloat16.md")
 (include "zicond.md")
 (include "sfb.md")
 (include "zc.md")
+(include "vector.md")
+;; Vendor extensions
+(include "thead.md")
 (include "corev.md")
+;; Pipeline models
+(include "generic.md")
 (include "xiangshan.md")
 (include "mips-p8700.md")
+(include "sifive-7.md")
+(include "sifive-p400.md")
+(include "sifive-p600.md")
+(include "generic-vector-ooo.md")
+(include "generic-ooo.md")