pedalboard: carry forward riscv64 patches to 0.9.26

Nightly version bump omitted the patches/pedalboard/<version> directory for
0.9.26, so the build's unconditional `git apply .../*.patch` step
failed with "No such file or directory" before any build/test ran.
Copied forward the same patch set from 0.9.25 (unchanged since then).

Author: luhenry

patches/pedalboard/0.9.26/0001-cmake-don-t-assume-x86-when-the-target-isn-t-ARM.patch

@@ -0,0 +1,48 @@
+From: RISE Project <info@riseproject.dev>
+Subject: [PATCH] cmake: don't assume x86 when the target isn't ARM
+
+The Linux branch of CMakeLists.txt has two if/else pairs that treat
+"not ARM" as "x86": one adds -march=native (or -mavx) and defines
+HAVE_AVX, the other keeps FFTW's AVX/SSE codelets and drops only the
+NEON ones. On any other architecture the build fails at
+simd-support/simd-avx.h with "compiling simd-avx.h without -mavx".
+
+Make both conditions test for x86 explicitly, so architectures without a
+vendored SIMD backend (riscv64, ppc64le, s390x) build the scalar FFTW
+codelets and get no architecture-specific compiler flags. JUCE already
+falls back to its scalar path when JUCE_USE_SIMD is 0.
+
+Upstream-Status: To upstream [not yet submitted; upstream builds no riscv64 wheels]
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index 89de0fa..f697bfc 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -203,7 +203,7 @@ elseif(UNIX AND NOT APPLE)
+     # Processor-specific optimizations (x86 vs ARM)
+     if(CMAKE_SYSTEM_PROCESSOR MATCHES "arm|aarch64")
+         add_compile_definitions(HAVE_NEON=1)
+-    else()
++    elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "x86_64|amd64|AMD64|i[3-6]86")
+         # Use -march=native for local builds to optimize for the current CPU,
+         # but use a portable baseline for CI builds to avoid "Illegal instruction" errors
+         # when ccache restores objects built on different runner hardware.
+@@ -214,6 +214,7 @@ elseif(UNIX AND NOT APPLE)
+         endif()
+         add_compile_definitions(HAVE_AVX)
+     endif()
++    # Any other architecture (riscv64, ppc64le, s390x, ...) builds without SIMD.
+     
+     # Additional Linux flags
+     list(APPEND ALL_INCLUDES "vendors/fftw3/api/" "vendors/fftw3/")
+@@ -317,8 +318,10 @@ function(collect_sources)
+         # Exclude files depending on architecture
+         if(CMAKE_SYSTEM_PROCESSOR MATCHES "arm|aarch64")
+             list(FILTER FFTW_SOURCES EXCLUDE REGEX ".*(avx|/sse).*")
+-        else()
++        elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "x86_64|amd64|AMD64|i[3-6]86")
+             list(FILTER FFTW_SOURCES EXCLUDE REGEX ".*neon.*")
++        else()
++            list(FILTER FFTW_SOURCES EXCLUDE REGEX ".*(avx|/sse|neon).*")
+         endif()
+         
+         # Exclude unused FFTW components