mesa/main: remove always-true define

We don't include this header anwhere where BPTC_BLOCK_DECODE isn't
already true, so let's remove it.

Acked-by: Marek Olšák <marek.olsak@amd.com>
Acked-by: Soroush Kashani <soroush.kashani@imgtec.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/18012>

src/mesa/main/texcompress_bptc.c

@@ -26,8 +26,6 @@
  * GL_ARB_texture_compression_bptc support.
  */
 
-#define BPTC_BLOCK_DECODE
-
 #include <stdbool.h>
 #include "texcompress.h"
 #include "texcompress_bptc.h"

src/mesa/main/texcompress_bptc_tmp.h

@@ -652,7 +652,6 @@ fetch_rgba_unorm_from_block(const uint8_t *block,
    apply_rotation(rotation, result);
 }
 
-#ifdef BPTC_BLOCK_DECODE
 static void
 decompress_rgba_unorm_block(int src_width, int src_height,
                             const uint8_t *block,
@@ -816,7 +815,6 @@ decompress_rgba_unorm(int width, int height,
       src += src_row_diff;
    }
 }
-#endif // BPTC_BLOCK_DECODE
 
 static int
 signed_unquantize(int value, int n_endpoint_bits)
@@ -1029,7 +1027,6 @@ fetch_rgb_float_from_block(const uint8_t *block,
    result[3] = 1.0f;
 }
 
-#ifdef BPTC_BLOCK_DECODE
 static void
 decompress_rgb_float_block(unsigned src_width, unsigned src_height,
                            const uint8_t *block,
@@ -1158,7 +1155,6 @@ decompress_rgb_float(int width, int height,
       src += src_row_diff;
    }
 }
-#endif // BPTC_BLOCK_DECODE
 
 static void
 write_bits(struct bit_writer *writer, int n_bits, int value)

src/util/format/u_format_bptc.c

@@ -29,7 +29,6 @@
 #include "util/format_srgb.h"
 #include "util/u_math.h"
 
-#define BPTC_BLOCK_DECODE
 #include "../../mesa/main/texcompress_bptc_tmp.h"
 
 void